training spamassassin

[ewok2]

Hello
I have install Spamassassin and had recieved a lot of spam. (despite the fact spamassassin was running)
I have launch the following command to train spamassassin :

sudo -u spamd sa-learn --showdots --spam /tmp/junk/cur/*

(previously I have moved my junk folder in "tmp" directory)

Now I did not recieve any spam :-)

But I would like to add a cron job to force spamassassin to learn with the content of all user Junk folder.

The Junk folder are in the following directory :

/var/vmail/"user"/Maildir/.Junk/cur

This directory is rw only for the user "vmail"

I could add a group with read/write on the directory and add a cron script with the above command but it seem's strange that nothing exist to do it?

Is there a better way ?

Thanks