[Creating New topic,replying] POST Error: Zero Sized Reply

Recently I added some posts to the forum and was receiving this error:
http://setupmyscript.com/Noname.png

ERROR
The requested URL could not be retrieved

While trying to retrieve the URL: https://vrip.forumotion.com/post

The following error was encountered:

Zero Sized Reply

Squid did not receive any data for this request.
Generated Wed, 03 Aug 2011 23:18:10 GMT by pcl-iwfcache02.plus.net (squid)


I am on the UK ISP PlusNet and read that this is the reason for this error with this site/forum (forumotion.com),
but It seems to not have any problem if I use chrome.... seems very odd to me or more like a foboff that because one is one plusnet it would go through a cache first and only be rejected/null post if using firefox... baffled

I have not encountered anything unusual yet. knock on wood!

I have noticed it allot more on the larger posts. ill just have to keep that in mind :s