with mail-mta/qmail-1.03-r15 one cannot choose which ip you want to use for sending mail with qmail-remote, but this seemed to be fixed in -r16. Altho with -r16 it still uses the default eth0 ip address. This patch "virtual-domain-outgoing-IP-address.patch" seems to do the same as as the "qmail-1.03-outgoing.ip-gentoo.diff" which was posted to the qmail team earlier. Altho the later used a file "outgoingip" to set the ip but I dont see any such ip configuration file in the patch included in -r16. The problem with this is that the IP address which selected from using 0.0.0.0 or the first ip on eth0 is not the same as what the hostname which is used for the HELO/EHLO command alot of remote smtp servers will reject your smtp connection. This is a big show stopper... Reproducible: Always Steps to Reproduce: 1. 2. 3.
I've closed bug 56744 as a duplicate of bug 98961. The new patch resolves the mail-from-domain and uses that IP address.