asterisk users - Dec 2005 - Asterisk Realtime 2 Servers calling each other

Hi guys I have a question, im trying asterisk realtime in 2 servers.  
Im trying to make calls from one server to another, example I call a  
sip registered in sip server 1 with a phone register in sip server2  
and both using the same database and family both use canreinvite=yes  
but still cant make the calls any ideas?