One postfix queue for mail sent via different accounts?

[Andreas Rippl <a.rippl@gmx.net>]

Hi list,

I have played around with this for a bit and have not come up with a
satisfying solution:

I have a Debian Sarge snapshot (from last Dec.) which is used
by User A (me) and User B (my girlfriend). I am using
mutt+fetchmail+postfix+procmail to do my mailing while she is using
evolution (local mbox for retrieval, comes together with my mail over
fetchmail and smtp to the mail provider for sending). 
Now, I would like to be able to use postfix with both my mailqueue 
(which I already do) and with her queue (which currently goes out 
directly from within evolution).

The problem is that we are both with the same mail provider, and using
postfix-tls, I don't seem to be able set up two accounts with the same 
provider. Googling around, I read that this is not possible at all, 
as postfix as an MTA is not the right place to separate the different 
origins. I also tried cutting out the relayhost altogether, but as I am
on dialup, mail is (understandably) always rejected by the recipient.

To recap: I would like to two local users, who both use a mail account 
with the same freemail provider, to use the same mail queue. This wish 
is due to dialup, as I want to avoid having to actively send/receive mail 
(from within evolution - the mutt way already works). Also, I am open to
different solutions altogether. For example, I have not looked at exim,
as I found the documentation not intuitive at all last time I looked.

Thanks for any hints,

Andreas