When using spark client or a jabber client with zimbra, we experience consistent disconnect and reconnects. This happens in different networks we tried.

On the same server, we have tried other jabber servers which seemed to work fine which eliminates network or server connection problems.

Any clue why this happens, and what I could do to try and rectify the issue? Also which log file does chat service error messages be logged to?

Zimbra version:
Release 5.0.9_GA_2533.RHEL5_20080815132719 CentOS5 FOSS edition