Duplicate headers recieved from server error - Chrome and FireFox

[HansK]

When using Chrome, or Firefox and replying to a post using the "Go advanced" option, we keep getting an error. It does not always happen with the quick reply feature, but certainly does when using the advanced text option. There is a thread on our forum that some other users have commented on here

http://www.hairrestorationnetwork.com/eve/164172-error-when-posting-firefox.html

Any help with this will be most welcome.

Thanks Hans

[HansK]

Anyone seen this? Seems odd that we are the only ones getting this type of error.