wine users - Jan 2011 - Ubuntu screen saver problem related to Wine

I got a new Dell XPS 15 laptop and installed Ubuntu 10.10 64bits and Wine
1.3.10.  A strange thing I found is that after a Wine program was started (even
after it was stopped), the screen saver does not activate.  I can actually force
it to activate from command line, but after a little while it gets deactivated
even though I never touched anything.  So I used "xev" to see what X
event might be causing the problem.  It turns out the following key event
triggers once in a while:

Code:
KeyPress event, serial 37, synthetic NO, window 0x5800001,
    root 0x15d, subw 0x0, time 15657297, (152,155), root:(184,204),
    state 0x0, keycode 235 (keysym 0x1008ff59, XF86Display), same_screen YES,
    XLookupString gives 0 bytes: 
    XmbLookupString gives 0 bytes: 
    XFilterEvent returns: False


Keycode 235 is related to the 2 keys controlling screen brightness - in my case
F4 and F5 without holding the Fn key. I am not sure what serial 37 means. If I
press F4 or F5 manually without Fn key, xev preports serial 45 rather than 37.

Note this does not happen in a session without starting any Wine program. 
Anyone know what might be causing the problem?