[Asterisk-Dev] setting up fromuser

[usman at user.iphonica.net]

hi all,

I have got a problem with asterisk "fromuser" field in sip.conf. Actually
I have got two asterisk servers communicating over sip. When a user from
Asterisk Server A calls a specific extension it is redirected to another
Asterisk Server B and that Asterisk Server B forwards it to a Soft-Switch.
Now the problem being that the other Soft-Switch takes CLI from the "FROM"
field of SIP Invite Packet. The Asterisk Server B puts "Asterisk" in the
from field when redirecting the call to Soft-Switch. If I use the
"fromuser" field then the CLI works but it is not dynamic. However in 
originating
call from Asterisk Server A the "from" field is correct. So my question is
that how can I make "fromuser" fild in sip.conf dynamic ? Means that
whatever is coming into ${CALLERIDNUM} should be assigned to fromuser in
sip.conf. Plz assist me in this problem.

khan.