Ok. I'd run across this under 10.0, and finally figured it all out, but had forgotten. So I went looking. Turns out the interface I'd used under 10.0 isn't there anymore.
Anyway, your culpret is msec (Mandrive Security). Which is pretty handy and all, can just cause some problems. If you check your /etc/cron.hourly, I bet you see it in there. Now, you can get rid of it (check cron.daily as well), or you can change its behavior. To do so, you'll need to know the msec level that you are running under (check /etc/sysconfig/msec under the SECURE_LEVEL variable). Once you know that, pop over to /usr/share/msec. In this directory are your configuration files. If you look in the perm file for your security level (mine is set to 3, so perm.3 for me), you'll see a listing of directories, owners, and permissions. When that cron job kicks off every hour, it sets the owner and permissions for those directories. Just find the home directory and set the permissions to what you want.
There might be a GUI interface for this, but I couldn't find one on my 2005LE system, though I remember it in the Control Center under 10.0.