Spam filtering increasingly useless with DSPAM - CriticalPath NOW please.

[#1]

This is not about the increasing amount of spam in general - I accept that it comes in waves but the general trend is upwards.  Nor is it about past mistakes which are now behind us.
However DSPAM is increasingly useless at marking spam or ham correctly.  I no longer attempt to train it because it seems to have lost the plot.
I download all email, nothing is blackholed or spambinned at the PN server.  I then run the mail through K9 here, and then apply rules based on K9's rating.
In the past 72 hours of 47 marked correctly as spam by K9 only 37 were marked as [-SPAM-] by PN - a false negative rate of 21%
DSPAM is also continuing to mark ham as [-SPAM-] - the false positive rate is lower, only 4% over the past 10 days, but I could have lost important emails if I left it to PN.  K9 has recognised all correctly so they end up in my inbox where they belong.
I have 3 other email accounts, all of which do much better - no false positives, and false negatives well below 1.5%.
Checking the headers on the spam of the 10 that DSPAM missed marked as X-DSPAM-Result: Innocent, CriticalPath marked all as X-MAA: Suspected Spam.
CriticalPath has not marked any of the false positives as suspected spam
So can we please get on with using CriticalPath and retiring DSPAM completely.
My mother-in-law, aged 87 has joined the ranks of silver surfers.  She is currently on dial-up and I was going to suggest she move to broadband, but I am certainly not prepared to recommend PlusNet while she is likely to see the sort of explicit subject lines that I get, and I am not going to post here
bobp

[#2]

Critical Path tagging with [-SPAM-] is due to be turned on on Monday.
If MIL had a specific named mailbox set up for her on Plusnet there is no reason she should receive any spam unless that email address fell in to the wrong hands. Two months ago I set up a new mailbox which I use with a particular client - to date it has received absolutely no spam whatsoever.

[#3]

Hi there,
As jelv says we'll be starting using Critical Path for tagging next week.
We're very keen to get both Critical Path and Postini live ASAP, but as I'm sure you'll appreciate we absolutely want to ensure that everything has been thoroughly tested before affecting customer mail.
If you sign up a new account, or give your mother-in-law a dedicated email address there's no reason you should start to receive spam, and making sure spam filtering is enabled will allow you to delete any that does start arriving before it gets downloaded (alternatively you could direct it to the SPAM folder so that you could check it if required).