VMWare 6.02 and Ubuntu 7.10 screen saver?

[Scott Ehrlich]

I have a user who freshly installed Ubuntu 7.10 desktop.   They also 
installed VMWare 6.02.

When they click the mouse on their Ubuntu desktop, the screen saver 
properly activates.  But, when they click the mouse in their VMWare 
session, the Ubuntu screen saver never activates.  This has been tried for 
both VMWare Player and Workstation.

I don't know if it makes any difference, but the VMWare Guest OS is 
Windows XP w/SP2.

Thanks for any insight.

Scott