ScriptUI.newImage() rollover does not seem to work

Hi

I'm trying to make rollover in newImage() to work but no success yet.

The main image is loaded just fine, but the image set for a rollover event does not load up when the mouse passes over the IconButton;

using this line code:

myPanel.grp.clearGroup.myButton.image = ScriptUI.newImage(IconClean,IconClean,IconClean,IconCleanHover);

IconClean is the main image and IconCleanHover is the rollover image.

both are loaded as binary string.

any ideas?

thanks

Liran