BuddyPress.org

I am having trouble with running bbPress 2.2.4 and BuddyPress 1.6.4 on the Custom Community 1.14 theme. I have disabled all other plugins and rebuilt permalinks to different structures, to no avail. The problem is replicated using the default BuddyPress theme.
The site is http://www.surprisecommunity.com
When my registered users click “Submit” to enter a topic or a reply, an error page results. It seems that there is some conflict in the slug/permalink configuration. The new topic/reply does post but not before the user is shown a page like this:

`
0

302 Found

Found
The document has moved here.
Additionally, a 302 Found
error was encountered while trying to use an ErrorDocument to handle the request.

HTTP/1.1 200 OK
Date: Tue, 19 Mar 2013 19:13:24 GMT
Content-Type: text/html; charset=UTF-8
Server: Nginx / Varnish
X-Powered-By: PHP/5.3.13
X-Pingback: http://www.surprisecommunity.com/xmlrpc.php
Expires: Wed, 11 Jan 1984 05:00:00 GMT
Cache-Control: no-cache, must-revalidate, max-age=0
Pragma: no-cache
Set-Cookie: bp-message=deleted; expires=Thu, 01-Jan-1970 00:00:01 GMT; path=/
Set-Cookie: bp-message-type=deleted; expires=Thu, 01-Jan-1970 00:00:01 GMT; path=/
Vary: Accept-Encoding
Content-Encoding: gzip
Transfer-Encoding: chunked
`
followed by a bunch of jibberish

My themes author thinks it may have to to with BuddyPress config.
Any ideas about what is going on??