asterisk users - May 2009 - dial out context from incoming iax trunk

Hello,
I am trying to make some test in connecting 2 asterisk with trunk.

I managed to call the 2 asterisk eachother via IAX trunk.
The problem is, i have a pri trunk over servera and i want to enable to
call that trunk via serverb too.
When i try to call i got the following error on servera

Frame Retry[000] -- OSeqno: 001 ISeqno: 002 Type: IAX     Subclass: REJECT
   Timestamp: 00006ms  SCall: 02968  DCall: 00559 [139.179.16.200:4569]
   CAUSE           : No such context/extension


As i understand there s a context problem with it.
I have default context with my both servers..So how can i add that context
to my other dialplans and make able to call it from other server too?