I love cutechat, it is miles ahead of any competitor. I have just finished setting it up for a dating site. The client loves it!

 

One of the testers cannot get the chat to work from her office, it works from home, and it works for all our other test users. But when she tries from her office (which is behind a corporate firewall) she gets a message "Connection Failed... This account is using. Please try again".

 

This isn't a showstopper for us, but if it is a firewall problem we want to put on explanation on the site, about why it may not work for some users.