diff --git a/src/common/uri/param/mod.rs b/src/common/uri/param/mod.rs
index 31f4cc1..ca1745c 100644
--- a/src/common/uri/param/mod.rs
+++ b/src/common/uri/param/mod.rs
@@ -169,13 +169,13 @@ pub mod tokenizer {
 
             let (rem, (_, name, value)) = tuple((
                 tag(";"),
-                take_while(I::is_token), //rfc3261 includes other chars as well, needs fixing..
+                take_while(I::is_token),
                 opt(map(
                     tuple((
                         tag("="),
                         alt((
                             recognize(delimited(tag("\""), take_until("\""), tag("\""))),
-                            take_while(I::is_token),
+                            take_while(I::is_param_value),
                         )),
                     )),
                     |t| t.1,
diff --git a/src/lib.rs b/src/lib.rs
index c1ff1e4..5fe3e97 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -317,6 +317,9 @@ pub trait AbstractInputItem<I>: nom::AsChar + std::cmp::PartialEq<I> + From<u8>
     fn is_alphabetic(c: I) -> bool;
     fn is_alphanumeric(c: I) -> bool;
     fn is_token(c: I) -> bool;
+    /// RFC 3261 §25.1: paramchar allows param-unreserved characters in addition to token chars.
+    /// param-unreserved = "[" / "]" / "/" / ":" / "&" / "+" / "$"
+    fn is_param_value(c: I) -> bool;
 }
 
 impl<'a> AbstractInput<'a, char> for &'a str {
@@ -337,6 +340,10 @@ impl AbstractInputItem<char> for char {
     fn is_token(c: char) -> bool {
         Self::is_alphanumeric(c) || "-.!%*_+`'~".contains(c)
     }
+
+    fn is_param_value(c: char) -> bool {
+        Self::is_token(c) || "[]/:&+$".contains(c)
+    }
 }
 
 impl<'a> AbstractInput<'a, u8> for &'a [u8] {
@@ -358,6 +365,10 @@ impl AbstractInputItem<u8> for u8 {
 
         is_alphanumeric(c) || "-.!%*_+`'~".contains(char::from(c))
     }
+
+    fn is_param_value(c: u8) -> bool {
+        Self::is_token(c) || b"[]/:&+$".contains(&c)
+    }
 }
 
 pub(crate) mod utils {
diff --git a/tests/headers/record_route/typed.rs b/tests/headers/record_route/typed.rs
index 392fda7..96d3574 100644
--- a/tests/headers/record_route/typed.rs
+++ b/tests/headers/record_route/typed.rs
@@ -50,6 +50,64 @@ mod display {
     }
 }
 
+mod param_values_with_colons {
+    use super::*;
+    use rsip::common::uri::param::{OtherParam, OtherParamValue};
+
+    /// Kamailio encodes internal routing info in Record-Route URI parameters
+    /// using values that contain SIP URIs (e.g. du=sip:host:port).
+    /// The colon must be preserved per RFC 3261 §25.1 (param-unreserved).
+    #[test]
+    fn kamailio_du_param_round_trip() -> Result<(), rsip::Error> {
+        let input = "<sip:82.202.218.130;lr=on;ftag=d4nwJ0jF;du=sip:95.143.188.49:5060;did=893.d6d1>";
+        let tokenizer = UriWithParamsListTokenizer::tokenize(input).unwrap().1;
+        let record_route: RecordRoute = tokenizer.try_into()?;
+        let uris = record_route.uris();
+
+        assert_eq!(uris.len(), 1);
+        let uri = &uris[0];
+
+        // Verify all params are preserved, including du with colons
+        assert_eq!(
+            uri.uri.params,
+            vec![
+                Param::Other(OtherParam::from("lr"), Some(OtherParamValue::from("on"))),
+                Param::Other(OtherParam::from("ftag"), Some(OtherParamValue::from("d4nwJ0jF"))),
+                Param::Other(
+                    OtherParam::from("du"),
+                    Some(OtherParamValue::from("sip:95.143.188.49:5060"))
+                ),
+                Param::Other(OtherParam::from("did"), Some(OtherParamValue::from("893.d6d1"))),
+            ]
+        );
+
+        // Verify round-trip preserves the full value
+        // UriWithParams::Display already wraps in angle brackets
+        let output = uri.to_string();
+        assert_eq!(output, input);
+
+        Ok(())
+    }
+
+    #[test]
+    fn param_value_with_slashes_and_colons() -> Result<(), rsip::Error> {
+        let input = "<sip:proxy.example.com;lr;dest=sip:10.0.0.1:5080/udp>";
+        let tokenizer = UriWithParamsListTokenizer::tokenize(input).unwrap().1;
+        let record_route: RecordRoute = tokenizer.try_into()?;
+        let uri = &record_route.uris()[0];
+
+        let dest_param = uri.uri.params.iter().find(|p| {
+            matches!(p, Param::Other(name, _) if name.to_string() == "dest")
+        });
+        assert!(dest_param.is_some());
+        if let Some(Param::Other(_, Some(val))) = dest_param {
+            assert_eq!(val.to_string(), "sip:10.0.0.1:5080/udp");
+        }
+
+        Ok(())
+    }
+}
+
 mod try_from_tokenizer {
     use super::*;