postfix and virtual mailusers ??

How do I configure my postfix to deliver mail from outside my domain
to local users?

My provider sends me (pop3) a couple of mails which are addressed to
my former mailaddress ((E-Mail Removed)). In newer days I have an own
domain (dl1sdr.de) and my postfix is configured to be responsible for
all mail to this domain.

If I configure postfix to use "abc.de" as a vitual domain in addition
to "dl1sdr.de" everything works fine, the mails to my former address
will be delivered to the correct alias. But every outgoing mail to
mail addresses with the domian "abc.de" will not leave my network.
Postfix means that every mail to "...@abc.de" is local.

Can I configure postfix to handle only SOME SPECIFIC addresses within
the virtual domain "abc.de" local? All other addresses to that domain
should be delivered to the relayhost outside my network. That would be
very nice.

Suse 7.3, postfix ver. 20010228pl04-20

Thanks for every hint.

Regards.
Heiko