[Serusers] How to use a numeric ID to call another UA at another server?

[Charles Wang]

Dear ALL:

My scenario is two domains(domainA, domainB), two SER sip server
(SER_A, SER_B) and two UAs (UA_A, UA_B).

If UA_A registers to SER_A using a numberic ID (886701234567) 
and another UA_B registers to SER_B using a numberic ID (886207654321). 

How can SER_A know to forward to call to UA_B under SER_B with only
numberic ID? Is it possible?

If it is impossible, now SER_A and SER_B using the same DB, does this
question have answer?
How can SER_A search the DB and find the UA_B's URI or
886207654321 at domainB.com with only 886207654321?

Can someone give me a ser.cfg to reference? Please....


Charles