vanishing pointer in 10.2.5

[Eytan Bercovitch]

I've recently installed OSX 10.25 on my G4 400 mac.  I notice that 
the mouse pointer vanishes from the screen for periods when it goes 
over certain windows (that seem to share the quality that they 
include spaces for typing in information).  Has anyone else noticed 
this in 10.2.5 (or previous OSX versions, though I never noticed it 
in previous versions myself)?

Thanks