I took a look at the dSPAM web pages. dSPAM has some good features. It can be integrated with the Exim mail router (which would make it very easy for Astaro's programmers to integrate it into a new ASG version). dSPAM is also reported to be very accurate, on the order of 99.8%.
It is too bad that this software is not included in ASG. To have to deploy a separate Linux box just for running dSPAM is a waste.
Yeah, dspam is pretty good, but probably the biggest drawback is that it does require accurate training for it to be effective. If you're not diligent about correcting misclassified emails, the accuracy quickly declines. On one account so far it is about 95% accurate, but another (which receives more mail and hence has had more training) is 99.8% accurate.
If you're looking for spam filtering out of the box, spamassassin works much better.
With a bit of thinking I think you could combine both to provide decent out of the box spam filtering along with the long term accuracy of dspam.
Is there anyone ho is running ASSP (Anti-Spam SMTP Proxy) or testing with it?
This program has a Automatic Bayesian corpus training.....
http://www.asspsmtp.org/wiki/Welcome
I've used DSPAM successfully with Exim in the past and absolutely loved it. With my recent move to OS X Server (uses postfix) I've opted to reimplement it. Positively awesome.
If they were to implement DSPAM in ASG, they should probably pre-train it with some corpus archive of spam/ham. There's some floating around that DSPAM folks use. It seems to bring up the effectiveness to about 70% ... (still better than the current spamassasin on ASG) if you use a global account and some honeypots, you can bring that up to 90%-ish. Personal training gets it the rest of the way.
Since Astaro has already implemented quarantines in the UI, it wouldn't be too difficult to recode it for DSPAM. They could even drop in the graphs and prefs in the end-user interface.
Currently I have Astaro picking up the obvious stuff, with DSPAM on OS X to get everything else. I just can't use 'person+spam' and 'person+ham' for training dspam currently due to ASG's SMTP proxy eliminating the '+' delimiter (see my other forum post on this topic).