Just found this add comment extension, it looks great but somehow it can't be installed to my joomla 1.5.6 website.

This is the error message I got when I tried to install this extension:

The server encountered an unexpected condition which prevented it from fulfilling the request.
The script had an error or it did not produce any output. If there was an error, you should be able to see it in the error log.

----------

I don't understand this error. Does it mean Jcomment has a conflict wit my server? and how can I solve this problem?