diff --git a/tokio-xmpp/src/connect.rs b/tokio-xmpp/src/connect.rs
index 2358aba..79f79de 100644
--- a/tokio-xmpp/src/connect.rs
+++ b/tokio-xmpp/src/connect.rs
@@ -11,7 +11,7 @@ pub trait AsyncReadAndWrite: AsyncRead + AsyncWrite + Unpin + Send {}
 impl<T: AsyncRead + AsyncWrite + Unpin + Send> AsyncReadAndWrite for T {}
 
 /// Trait that must be extended by the implementation of ServerConnector
-pub trait ServerConnectorError: std::error::Error + Send {}
+pub trait ServerConnectorError: std::error::Error + Sync + Send {}
 
 /// Trait called to connect to an XMPP server, perhaps called multiple times
 pub trait ServerConnector: Clone + core::fmt::Debug + Send + Unpin + 'static {