Tsung test with openfire


I’m currently doing load tests on my open fire. Unfortunately i have a problem, that happens in every test. Several minutes into my test (ca. 12) openfire starts closing my user sessions. the only logmessage i could find was this:

No ACK was received when sending stanza to: org.jivesoftware.openfire.nio.NIOConnection@7f28a943 MINA Session: (SOCKET, R: /, L: /, S:

That of cause kills my test. later messages (like joining muc-rooms) gain another warning:

Ignoring available presence packet of closed session… (because the user session was closed earlier.

What goes wrong in my server?