Problem with Jabber transport

I have a problem with jabber gadu gadu transport in em Client. When i try to send someone message i recive an email from google with error that they cant deliver my email to

can you please specify what jabber provider do you use for the transport?

I thought that google is the provider (
So I only added a new contact by the:
Instant messenging --> add contact --> choose Gadu Gadu --> enter number
And it thought that should work.
Do I need to do something else?