So, I have been making sure that my users properly move spam mail into their "Junk" folder and move ham mail out of their "junk" folder.

how can I validate that satrain is being done properly?

I see that there is a log called spamtrain.log I browsed it to see if I could tell...

I see the following in the log:
20080608230004 Starting spam/ham extraction from system accounts.
[] INFO: Total messages processed: 0
[] INFO: Total messages processed: 0
20080608230018 Finished extracting spam/ham from system accounts.

Am I missing a step here?