AVAST, screensaver, ZA autolock

I use to set my screensaver to “blank” and to set zonealarm’s automatic lock to “when screensaver activates”. With Avast! among the acreensavers a couple of things go wrong.

Screensaver and ZA set as above: no screensaver, no automatic lock.(If set to x minutes autolock works, but that’s not how I want it).

With another screensaver and ZA set to autolock at the same time: screensaver yes (goes to “blank” after some time, however) but no autolock by ZA.

XP pro, ZA, aVAST 4 home.

Anybody have the same experience and/or a solution?

Thanks in advance

Update to avast 5 and see if the problem is solved.