Server updated to beta5.
And you don't need to update the client every time, it's not SA-MP which needs a new client when a single character in the sourcecode has been changed. (Well, not literally, but you got the idea )
Ohax!
Long time ago since the last update, but the latest TS3 beta server (beta 15) requires also a client update (beta 11) before you can connect.
In previous builds you could connect with each server version with all client versions.