[afnog] help postfix configuration

[David Chima]

Hello wonderful people of Afnog,
I am trying to migrate from sendmail to postfix and I need a push somewhere.

I have a server that is running RedHat Linux 9.0 and with sendmail. This server receives mail for some 
domains but not others. eg it receives mail for
qqq.mw
ppp.qqq.mw
jjj.qqq.mw

but not for 

ddd.qqq.mw
yyy.qqq.mw

qqq.mw is the local domain for this server. All mail for these subdomains passes through this server. 
What I want is that local mail and those from postmaster should be local to this machine but only forward mail 
for the other subdomains ddd.qqq.mw and yyy.qqq.mw to their respective servers.

Is there someone who can give me a push here.

Regards

David