postfix experts?

[Paul Goyette <paul%whooppee.com@localhost>]

I'm trying to get dspam set up to use a single system-wide alias for 
"relearning" messages.  I've added the following in my aliases database:

is-spam:        "|/usr/pkg/bin/dspam --user $user --class=spam --source=error"
is-not-spam:    "|/usr/pkg/bin/dspam --user $user --class=innocent 
--source=error"

But it seems that postfix/local isn't substituting $user, and I'm 
getting a non-delivery message.

Here's the entries from /var/log/maillog

Apr  3 14:30:08 screamer postfix/pickup[24401]: 8A6A12471BA: uid=1000 
from=<paul>
Apr  3 14:30:08 screamer postfix/cleanup[22173]: 8A6A12471BA: 
message-id=<Pine.NEB.4.64.1204031430010.21744%screamer.whooppee.com@localhost>
Apr  3 14:30:08 screamer postfix/qmgr[366]: 8A6A12471BA: 
from=<paul%whooppee.com@localhost>, size=3388, nrcpt=1 (queue active)
Apr  3 14:30:08 screamer dspam[6236]: Unable to determine the destination user
Apr  3 14:30:08 screamer postfix/local[23594]: 8A6A12471BA: 
to=<is-not-spam%whooppee.com@localhost>, relay=local, delay=0.12, 
delays=0.07/0.02/0/0.04, dsn=5.3.0, status=bounced (Command died with status 1: 
"/usr/pkg/bin/dspam --user $user --class=innocent --source=error". Command output: 
6236: [04/03/2012 14:30:08] Unable to determine the destination user Syntax: dspam 
[--client|--daemon] --mode=[toe|tum|teft|notrain] --user [user1 user2 ... userN] 
[--feature=[ch,no,wh,tb=N,sbph]] [--class=[spam|innocent]] 
[--source=[error|corpus|inoculation]] [--profile=[PROFILE]] [--deliver=[spam,innocent,summary]] 
[--process|--classify] [--stdout] [passthru-arguments] )
Apr  3 14:30:08 screamer postfix/bounce[11399]: 8A6A12471BA: sender 
non-delivery notification: 998292471BC
Apr  3 14:30:08 screamer postfix/qmgr[366]: 8A6A12471BA: removed


I know I can make it work by setting up a pair of aliases for each user, 
and embed the actual value of $user, but that's not really a scalable 
solution.

Any hints?


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| Paul Goyette     | PGP Key fingerprint:     | E-mail addresses:       |
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| Network Engineer | 0786 F758 55DE 53BA 7731 | pgoyette at juniper.net |
| Kernel Developer |                          | pgoyette at netbsd.org  |
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