The same here
Debian etch 4.0 , 32 bit
E6600 , 4 GB Ram
The server was nearly full 22 / 24 , then the server feel laggy and the ping increased. One Core of the dual core were at 99,9% and then the same happend, alle players lose their connections and the server were unreachable. (vCTF game)
In the game before with me + 3 bots in TDM, no problems.
*Edit*
I run several servers and the server went down after ~10 minutes. It's regardless if the map restartet or the server is full / low, after the time the server geht high cpu usage, lag and player disconnects.