[horde] IMP trying to expand all addresses?

[Jason Dixon]

When composing a message, IMP is reporting the following error upon  
submit:

"There was an error sending your message: unable to add recipient  
[someone at gmail.com]: Invalid response code received from server"

This doesn't happen if it's an address inside our own mail domain.   
Any ideas?

Thanks,

--
Jason Dixon
DixonGroup Consulting
http://www.dixongroup.net