Allowing authenticated users to relay via kolab postfix

[Munson, Eric]

All,

I am attempting to use a postfix configuration on my local desktop to 
relay via my Kolab 3.2 install.  I have setup my sasl authentication on 
my desktop properly (I think) but I keep getting rejected by the kolab 
server with the message:

Client host rejected: Access denied (in reply to RCPT TO command)

On the server I see:

NOQUEUE: reject: RCPT from my.external.domain.net[X.X.X.X]: 554 5.7.1 
<my.external.domain.net[X.X.X.X]>: Client host rejected: Access denied; 
from=<me at mydomain.net> to=<me at mydomain.net> proto=ESMTP 
helo=<desktopname>

What am I doing wrong?

Thanks,
Eric