http://bugs.winehq.org/show_bug.cgi?id=12962
--- Comment #7 from Mel mel@raumkraut.net 2009-08-14 04:26:15 --- After experiencing the same thing with EVE Online (thus being unable to target objects with the left control + click), I noticed that using my caps-lock key instead worked just fine - I have caps-lock mapped as "an additional control". Indeed, turning this caps-lock remap off causes the normal left-control to work as expected.
Using xev I see that when caps-lock is so mapped, both it and left control output the same keysym (0xffe3, Control_L). Perhaps there is something within either wine or compiz which expects a keysym to only be associated with a single keycode...?
And Sven; no, you're thinking of Alt+Click, which is one of the first things I change on any new set up.