diff --git a/Cargo.lock b/Cargo.lock
index 788cf7d8..3123920c 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -989,16 +989,16 @@ dependencies = [
 
 [[package]]
 name = "calcard"
-version = "0.1.0"
+version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "75eaecaebc21cf56381d401db71ed288d61f3fcbb880c777e08cab2f82dfc0ab"
+checksum = "8e16f081c4da49b29187103679784b4dcf2fbda52e9b519388c397cb58414e5a"
 dependencies = [
  "ahash",
  "chrono",
  "chrono-tz",
  "hashify",
  "mail-builder",
- "mail-parser 0.10.2",
+ "mail-parser",
  "rkyv",
  "serde",
 ]
@@ -1289,7 +1289,7 @@ dependencies = [
  "libc",
  "mail-auth",
  "mail-builder",
- "mail-parser 0.11.0",
+ "mail-parser",
  "mail-send",
  "md5",
  "nlp",
@@ -1776,7 +1776,7 @@ dependencies = [
  "compact_str",
  "hashify",
  "hyper 1.6.0",
- "mail-parser 0.11.0",
+ "mail-parser",
  "quick-xml 0.37.5",
  "rkyv",
  "serde",
@@ -1974,7 +1974,7 @@ dependencies = [
  "jmap_proto",
  "ldap3",
  "mail-builder",
- "mail-parser 0.11.0",
+ "mail-parser",
  "mail-send",
  "md5",
  "nlp",
@@ -2252,7 +2252,7 @@ dependencies = [
  "hashify",
  "jmap_proto",
  "mail-builder",
- "mail-parser 0.11.0",
+ "mail-parser",
  "nlp",
  "rand 0.8.5",
  "rasn",
@@ -3174,7 +3174,7 @@ dependencies = [
  "jmap_proto",
  "mail-auth",
  "mail-builder",
- "mail-parser 0.11.0",
+ "mail-parser",
  "mail-send",
  "mime",
  "pkcs8",
@@ -3576,7 +3576,7 @@ dependencies = [
  "imap_proto",
  "indexmap 2.9.0",
  "jmap_proto",
- "mail-parser 0.11.0",
+ "mail-parser",
  "mail-send",
  "md5",
  "nlp",
@@ -3600,7 +3600,7 @@ dependencies = [
  "compact_str",
  "hashify",
  "jmap_proto",
- "mail-parser 0.11.0",
+ "mail-parser",
  "store",
  "tokio",
  "trc",
@@ -3860,7 +3860,7 @@ dependencies = [
  "lz4_flex",
  "mail-auth",
  "mail-builder",
- "mail-parser 0.11.0",
+ "mail-parser",
  "mail-send",
  "nlp",
  "p256",
@@ -3916,7 +3916,7 @@ dependencies = [
  "compact_str",
  "fast-float",
  "hashify",
- "mail-parser 0.11.0",
+ "mail-parser",
  "rkyv",
  "serde",
  "serde_json",
@@ -4332,7 +4332,7 @@ dependencies = [
  "flate2",
  "hickory-resolver",
  "mail-builder",
- "mail-parser 0.11.0",
+ "mail-parser",
  "quick-xml 0.37.5",
  "quick_cache",
  "rand 0.8.5",
@@ -4354,16 +4354,6 @@ dependencies = [
  "gethostname",
 ]
 
-[[package]]
-name = "mail-parser"
-version = "0.10.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "187a2b93c4c8c32f552ee06c2d99915e575de2fc7e04b07891c9edfee5b8edd6"
-dependencies = [
- "encoding_rs",
- "hashify",
-]
-
 [[package]]
 name = "mail-parser"
 version = "0.11.0"
@@ -4405,7 +4395,7 @@ dependencies = [
  "imap",
  "imap_proto",
  "jmap_proto",
- "mail-parser 0.11.0",
+ "mail-parser",
  "mail-send",
  "md5",
  "parking_lot",
@@ -4508,7 +4498,7 @@ dependencies = [
  "jmap_proto",
  "lz4_flex",
  "mail-auth",
- "mail-parser 0.11.0",
+ "mail-parser",
  "nlp",
  "rkyv",
  "serde",
@@ -5467,7 +5457,7 @@ dependencies = [
  "email",
  "imap",
  "jmap_proto",
- "mail-parser 0.11.0",
+ "mail-parser",
  "mail-send",
  "rustls 0.23.27",
  "store",
@@ -7296,7 +7286,7 @@ dependencies = [
  "email",
  "hkdf",
  "jmap_proto",
- "mail-parser 0.11.0",
+ "mail-parser",
  "memory-stats",
  "p256",
  "reqwest 0.12.15",
@@ -7421,7 +7411,7 @@ dependencies = [
  "fancy-regex",
  "hashify",
  "mail-builder",
- "mail-parser 0.11.0",
+ "mail-parser",
  "rkyv",
  "serde",
 ]
@@ -7508,7 +7498,7 @@ dependencies = [
  "lru-cache",
  "mail-auth",
  "mail-builder",
- "mail-parser 0.11.0",
+ "mail-parser",
  "mail-send",
  "md5",
  "nlp",
@@ -7593,7 +7583,7 @@ dependencies = [
  "infer 0.19.0",
  "mail-auth",
  "mail-builder",
- "mail-parser 0.11.0",
+ "mail-parser",
  "mail-send",
  "nlp",
  "psl",
@@ -7684,7 +7674,7 @@ dependencies = [
  "indicatif",
  "jmap-client",
  "mail-auth",
- "mail-parser 0.11.0",
+ "mail-parser",
  "num_cpus",
  "prettytable-rs",
  "pwhash",
@@ -7946,7 +7936,7 @@ dependencies = [
  "jmap-client",
  "jmap_proto",
  "mail-auth",
- "mail-parser 0.11.0",
+ "mail-parser",
  "mail-send",
  "managesieve",
  "migration",
@@ -8467,7 +8457,7 @@ dependencies = [
  "compact_str",
  "event_macro",
  "mail-auth",
- "mail-parser 0.11.0",
+ "mail-parser",
  "parking_lot",
  "reqwest 0.12.15",
  "rkyv",
diff --git a/crates/common/Cargo.toml b/crates/common/Cargo.toml
index ba315e29..1780ba4e 100644
--- a/crates/common/Cargo.toml
+++ b/crates/common/Cargo.toml
@@ -19,7 +19,7 @@ mail-auth = { version = "0.7" }
 mail-send = { version = "0.5", default-features = false, features = ["cram-md5", "ring", "tls12"] }
 smtp-proto = { version = "0.1", features = ["rkyv"] }
 dns-update = { version = "0.1" }
-calcard = { version = "0.1", features = ["rkyv"] }
+calcard = { version = "0.1.1", features = ["rkyv"] }
 ahash = { version = "0.8.2", features = ["serde"] }
 parking_lot = "0.12.1"
 regex = "1.7.0"
diff --git a/crates/dav-proto/Cargo.toml b/crates/dav-proto/Cargo.toml
index 537fb922..6dfc46cc 100644
--- a/crates/dav-proto/Cargo.toml
+++ b/crates/dav-proto/Cargo.toml
@@ -7,7 +7,7 @@ edition = "2021"
 trc = { path = "../trc" }
 hashify = "0.2.6"
 quick-xml = "0.37.2"
-calcard = { version = "0.1", features = ["rkyv"] }
+calcard = { version = "0.1.1", features = ["rkyv"] }
 mail-parser = { version = "0.11", features = ["full_encoding", "rkyv"] }
 hyper = "1.6.0"
 rkyv = { version = "0.8.10", features = ["little_endian"] }
@@ -15,7 +15,7 @@ chrono = { version = "0.4.40", features = ["serde"], optional = true }
 compact_str = "0.9.0"
 
 [dev-dependencies]
-calcard = { version = "0.1", features = ["serde", "rkyv"] }
+calcard = { version = "0.1.1", features = ["serde", "rkyv"] }
 serde = { version = "1.0.217", features = ["derive"] }
 serde_json = "1.0.138"
 chrono = { version = "0.4.40", features = ["serde"] }
diff --git a/crates/dav-proto/src/lib.rs b/crates/dav-proto/src/lib.rs
index d5841c06..bfb92c7a 100644
--- a/crates/dav-proto/src/lib.rs
+++ b/crates/dav-proto/src/lib.rs
@@ -4,6 +4,7 @@
  * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-SEL
  */
 
+use calcard::vcard::VCardVersion;
 use compact_str::{CompactString, ToCompactString};
 use trc::Value;
 
@@ -40,6 +41,7 @@ pub struct RequestHeaders<'x> {
     pub content_type: Option<&'x str>,
     pub destination: Option<&'x str>,
     pub lock_token: Option<&'x str>,
+    pub max_vcard_version: Option<VCardVersion>,
     pub overwrite_fail: bool,
     pub no_timezones: bool,
     pub ret: Return,
diff --git a/crates/dav-proto/src/parser/header.rs b/crates/dav-proto/src/parser/header.rs
index 08e19088..d6238376 100644
--- a/crates/dav-proto/src/parser/header.rs
+++ b/crates/dav-proto/src/parser/header.rs
@@ -4,6 +4,8 @@
  * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-SEL
  */
 
+use calcard::vcard::VCardVersion;
+
 use crate::{Condition, Depth, If, RequestHeaders, ResourceState, Return, Timeout};
 
 impl<'x> RequestHeaders<'x> {
@@ -82,6 +84,23 @@ impl<'x> RequestHeaders<'x> {
                 }
                 return true;
             },
+            "Accept" => {
+                for value in value.split(',') {
+                    if value.trim().starts_with("text/vcard") {
+                        if let Some(version) = value.split_once("version=")
+                                               .and_then(|(_, version)| VCardVersion::try_parse(version.trim())) {
+                            if let Some(max_vcard_version) = &mut self.max_vcard_version {
+                                if version > *max_vcard_version {
+                                    *max_vcard_version = version;
+                                }
+                            } else {
+                                self.max_vcard_version = Some(version);
+                            }
+                        }
+                    }
+                }
+                return true;
+            },
             _ => {}
         );
 
diff --git a/crates/dav/Cargo.toml b/crates/dav/Cargo.toml
index 3eb4608f..64d5df0d 100644
--- a/crates/dav/Cargo.toml
+++ b/crates/dav/Cargo.toml
@@ -14,7 +14,7 @@ directory = { path = "../directory" }
 http_proto = { path = "../http-proto" }
 jmap_proto = { path =  "../jmap-proto" }
 trc = { path = "../trc" }
-calcard = { version = "0.1", features = ["rkyv"] }
+calcard = { version = "0.1.1", features = ["rkyv"] }
 hashify = { version = "0.2" }
 hyper = { version = "1.0.1", features = ["server", "http1", "http2"] }
 percent-encoding = "2.3.1"
diff --git a/crates/dav/src/card/get.rs b/crates/dav/src/card/get.rs
index c755a6b3..284ada98 100644
--- a/crates/dav/src/card/get.rs
+++ b/crates/dav/src/card/get.rs
@@ -105,7 +105,14 @@ impl CardGetRequestHandler for Server {
             .with_etag(etag)
             .with_last_modified(Rfc1123DateTime::new(i64::from(card.modified)).to_string());
 
-        let vcard = card.card.to_string();
+        let mut vcard = String::with_capacity(128);
+        let _ = card.card.write_to(
+            &mut vcard,
+            headers
+                .max_vcard_version
+                .or_else(|| card.card.version())
+                .unwrap_or_default(),
+        );
 
         if !is_head {
             Ok(response.with_binary_body(vcard))
diff --git a/crates/dav/src/card/query.rs b/crates/dav/src/card/query.rs
index ac3c63fa..90e58a60 100644
--- a/crates/dav/src/card/query.rs
+++ b/crates/dav/src/card/query.rs
@@ -13,7 +13,8 @@ use crate::{
     },
 };
 use calcard::vcard::{
-    ArchivedVCard, ArchivedVCardEntry, ArchivedVCardParameter, VCardParameterName,
+    ArchivedVCard, ArchivedVCardEntry, ArchivedVCardParameter, VCardParameterName, VCardProperty,
+    VCardVersion,
 };
 use common::{Server, auth::AccessToken};
 use dav_proto::{
@@ -200,22 +201,30 @@ fn find_parameter<'x>(
 pub(crate) fn serialize_vcard_with_props(
     card: &ArchivedVCard,
     props: &[CardDavPropertyName],
+    version: Option<VCardVersion>,
 ) -> String {
+    let mut vcard = String::with_capacity(128);
+    let version = version.or_else(|| card.version()).unwrap_or_default();
     if !props.is_empty() {
-        let mut vcard = String::with_capacity(128);
         let _ = write!(&mut vcard, "BEGIN:VCARD\r\n");
+        let is_v4 = matches!(version, VCardVersion::V4_0);
 
         for entry in card.entries.iter() {
             for item in props {
                 if entry.name == item.name && entry.group == item.group {
-                    let _ = entry.write_to(&mut vcard, !item.no_value);
+                    if item.name != VCardProperty::Version {
+                        let _ = entry.write_to(&mut vcard, !item.no_value, is_v4);
+                    } else {
+                        let _ = write!(&mut vcard, "VERSION:{version}\r\n");
+                    }
                     break;
                 }
             }
         }
         let _ = write!(&mut vcard, "END:VCARD\r\n");
-        vcard
     } else {
-        card.to_string()
+        let _ = card.write_to(&mut vcard, version);
     }
+
+    vcard
 }
diff --git a/crates/dav/src/common/mod.rs b/crates/dav/src/common/mod.rs
index 4717cad0..dbfb9a08 100644
--- a/crates/dav/src/common/mod.rs
+++ b/crates/dav/src/common/mod.rs
@@ -6,7 +6,7 @@
 
 use calcard::{
     icalendar::{ICalendarComponentType, ICalendarParameterName, ICalendarProperty},
-    vcard::VCardParameterName,
+    vcard::{VCardParameterName, VCardVersion},
 };
 use dav_proto::{
     Depth, RequestHeaders, Return,
@@ -35,7 +35,7 @@ pub mod lock;
 pub mod propfind;
 pub mod uri;
 
-#[derive(Default, Debug)]
+#[derive(Debug)]
 pub(crate) struct DavQuery<'x> {
     pub uri: &'x str,
     pub resource: DavQueryResource<'x>,
@@ -43,6 +43,7 @@ pub(crate) struct DavQuery<'x> {
     pub sync_type: SyncType,
     pub depth: usize,
     pub limit: Option<u32>,
+    pub max_vcard_version: Option<VCardVersion>,
     pub ret: Return,
     pub depth_no_root: bool,
     pub expand: bool,
@@ -158,7 +159,10 @@ impl<'x> DavQuery<'x> {
             ret: headers.ret,
             depth_no_root: headers.depth_no_root,
             uri: headers.uri,
-            ..Default::default()
+            max_vcard_version: headers.max_vcard_version,
+            sync_type: Default::default(),
+            limit: Default::default(),
+            expand: Default::default(),
         }
     }
 
@@ -176,7 +180,11 @@ impl<'x> DavQuery<'x> {
             ret: headers.ret,
             depth_no_root: headers.depth_no_root,
             uri: headers.uri,
-            ..Default::default()
+            max_vcard_version: headers.max_vcard_version,
+            sync_type: Default::default(),
+            depth: Default::default(),
+            limit: Default::default(),
+            expand: Default::default(),
         }
     }
 
@@ -196,7 +204,10 @@ impl<'x> DavQuery<'x> {
             ret: headers.ret,
             depth_no_root: headers.depth_no_root,
             uri: headers.uri,
-            ..Default::default()
+            max_vcard_version: headers.max_vcard_version,
+            sync_type: Default::default(),
+            depth: Default::default(),
+            expand: Default::default(),
         }
     }
 
@@ -220,7 +231,11 @@ impl<'x> DavQuery<'x> {
             ret: headers.ret,
             depth_no_root: headers.depth_no_root,
             uri: headers.uri,
-            ..Default::default()
+            sync_type: Default::default(),
+            depth: Default::default(),
+            limit: Default::default(),
+            max_vcard_version: Default::default(),
+            expand: Default::default(),
         }
     }
 
@@ -249,6 +264,7 @@ impl<'x> DavQuery<'x> {
             depth_no_root: headers.depth_no_root,
             expand: false,
             uri: headers.uri,
+            max_vcard_version: headers.max_vcard_version,
         }
     }
 
@@ -277,7 +293,9 @@ impl<'x> DavQuery<'x> {
             depth_no_root: headers.depth_no_root,
             expand: true,
             uri: headers.uri,
-            ..Default::default()
+            sync_type: Default::default(),
+            limit: Default::default(),
+            max_vcard_version: headers.max_vcard_version,
         }
     }
 
diff --git a/crates/dav/src/common/propfind.rs b/crates/dav/src/common/propfind.rs
index 69757954..47757f6a 100644
--- a/crates/dav/src/common/propfind.rs
+++ b/crates/dav/src/common/propfind.rs
@@ -1191,6 +1191,9 @@ impl PropFindRequestHandler for Server {
                                 DavValue::CData(serialize_vcard_with_props(
                                     &card.inner.card,
                                     items,
+                                    query
+                                        .max_vcard_version
+                                        .or_else(|| card.inner.card.version()),
                                 )),
                             ));
                         }
diff --git a/crates/dav/src/principal/matching.rs b/crates/dav/src/principal/matching.rs
index 66c34dab..905f3ff3 100644
--- a/crates/dav/src/principal/matching.rs
+++ b/crates/dav/src/principal/matching.rs
@@ -69,7 +69,10 @@ impl PrincipalMatching for Server {
                                 ret: headers.ret,
                                 depth_no_root: headers.depth_no_root,
                                 uri: headers.uri,
-                                ..Default::default()
+                                sync_type: Default::default(),
+                                limit: Default::default(),
+                                max_vcard_version: Default::default(),
+                                expand: Default::default(),
                             },
                         )
                         .await;
diff --git a/crates/groupware/Cargo.toml b/crates/groupware/Cargo.toml
index d1e2c136..54bc0e3c 100644
--- a/crates/groupware/Cargo.toml
+++ b/crates/groupware/Cargo.toml
@@ -12,7 +12,7 @@ jmap_proto = { path =  "../jmap-proto" }
 trc = { path = "../trc" }
 directory = { path =  "../directory" }
 dav-proto = { path =  "../dav-proto" }
-calcard = { version = "0.1", features = ["rkyv"] }
+calcard = { version = "0.1.1", features = ["rkyv"] }
 hashify = "0.2"
 tokio = { version = "1.45", features = ["net", "macros"] }
 rkyv = { version = "0.8.10", features = ["little_endian"] }
diff --git a/tests/Cargo.toml b/tests/Cargo.toml
index b65925ea..8bd7aee9 100644
--- a/tests/Cargo.toml
+++ b/tests/Cargo.toml
@@ -29,7 +29,7 @@ imap = { path = "../crates/imap", features = ["test_mode"] }
 imap_proto = { path = "../crates/imap-proto" }
 dav = { path = "../crates/dav", features = ["test_mode"] }
 dav-proto = { path = "../crates/dav-proto", features = ["test_mode"] }
-calcard = { version = "0.1", features = ["rkyv"] }
+calcard = { version = "0.1.1", features = ["rkyv"] }
 groupware = { path = "../crates/groupware", features = ["test_mode"] }
 http = { path = "../crates/http", features = ["test_mode", "enterprise"] }
 http_proto = { path = "../crates/http-proto" }