DSPAM creates a directory ~/.dspam/ where it stores everything: your hash database, signature information, and more importantly, logging. By viewing the log, you can check whether your filters (scanning and retraining) work.
1152618649 I Kimberly Green 44b3909987321804284693 Copies of swiss watches Delivered
1152636046 S "Nicholas" 44b3d48e89785083819021 Need medicine? All here! Quarantined <000001c6a4f3$77c44f00$0100007f@doghouse1>
A normal log would look something like the above. It shows two messages scanned, one seen as innocent, the other as spam.
Retraining is also logged and shows the letters M for misclassified (spam which was missed), and F for false positives (good mail which was seen as spam).
Another file you can look at, are the .stats file. This file contains your current statistics and allow you to see how well your spamfilter is doing. You can read the file in two manners, either by simply viewing the .stats file in your dspam profile directory (~/.dspam), or by typing in the command dspam_stats.
The documentation of DSPAM will tell you more about the meaning of the numbers, and how to correctly calculate your accuracy levels.
