Dear Sir

I have found a error with my Zimbra Open Source Version (zcs-8.0.0_GA_5434.UBUNTU12_64.20120907144631) running on Ubuntu 12.04.1 LTS. when i try to access Zimbra Admin panel from any web browser gives following Error

Internal Server Error

The server has encountered an internal error.

when i restart the Zimbra Service (zmcontrol restart) every things working perfectly. but it appearing time to time. no any error logs are found.

Kindly Please any one guide me how to fix this issue.