When I IM some online people, it sometimes says they went offline but they keep IMing me. Why?

[Steel Zehetbauer]

So I was talking to a few of my friends, and mid-conversation after I IM them it instantly retorts with "This person is offline", but they continue messaging me.  Every time I type after that it says the person is offline, and I don't know that they get  my messages.

 

I use Phoenix Firestorm.  Is this a known issue at all, or just some horrible anomoly?  I relogged and it didn't change anything.

[valerie Inshan]

I couldn't find any JIRA reporting such an issue. I would suggest you contact the Forestorm/Phoenix support team:

http://www.phoenixviewer.com/support.php

[Ry0ta Exonar]

Isn't there a chance they were actually offline and replying to your offline IM via e-mail?