Trying to use the 'Screen sharing' function within AnyMeeting

At first the Firewall blocked x-fcs content type, so allowed that

Now it is blocking because of the following:

2012-07-09 09:12:07 Deny 10.201.202.230 216.157.74.225 http/tcp 52679 80 1-Trusted 0-External ProxyDeny: HTTP Invalid Status-Line Format (Outgoing-00) Outgoing proc_id="http-proxy" rc="594" proxy_act="Outgoing" line="\xb1\x8a\xe8B\x9e\x14\xd3\x16\x87\x8e:\xe1\x aed\xe3Z\xa7\xc4F\x9e\xc4(\xfc\xbc\x9b\xa6\xc1\xae h\xf2\xcf\xe6\x93\xd5\xfe\x06\x97`fx\xb3|\x1c\xaa\ xa6\xcbU\x22\xcf\x8d \x15\xbf\xdcx\x10\x5c\x14\xd3\xe12]\xfe6d\x0a" msg_id="262150" Traffic
Any ideas? Watchguard firewall