I'm having trouble sending e-mail to a certain provider in the NL (KPN) where our e-mail bounces with a 550 5.7.1 error.
I have tried in vein to contact someone at this provider who knew anything about their e-mail/anti spam servers so that is a dead end.
We are relaying our e-mail through a postfix server which is acting as border gateway, there is also an exchange server relaying through this gateway which is unaffected, which means the 'problem' is with GW. (obviously this provider has their servers configured in a poor way or I would not be able to e-mail the rest of the world..)
The e-mail bounces before it gets to the DATA bit and I have narrowed it down to the RCPT TO: line.

RCPT TO:<xxxx@yyyy.nl> NOTIFY=SUCCESS,FAILURE ORCPT=rfc822;groupwise-xxxx@yyyy.nl:1:1

More specifically to the ':1:1' bit. Does anyone have any idea what GWIA setting causes it to add this ? I'm pretty sure there are more GroupWise systems in this country that do not seem to be affected or it would be a known issue .. When i look at Exchange it does not add anything after the RCPT TO address.

This is our agents/share/gwia.cfg (with info edited out)

--home /var/opt/novell/groupwise/mail/domain/wpgate/gwia
--dhome /var/opt/novell/groupwise/mail/domain/wpgate/gwia
--hn GroupWise.domain.nl
--mudas 2
--sd 8
--rd 16
--p 10
--te 2
--tg 5
--tc 5
--tr 5
--td 3
--tt 10
--pt 10
--it 10
--ldapthrd 10
--st 4
--rt 4
--dsnage 4
--mh w.x.y.z
--httpport 9850