It seems there is already a patch for Wine for this so should be fairly trivial to roll that patch back into cxover.
Taken from the following URL: http://appdb.winehq.org/objectManager.php?sClass=version&iId=25096
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How to get mouse input working
raw3.patch from bug 20395 with WINE 1.5.9 from git is required to get any ARMA II-based games to recognize mouse input (clicks).
The following should be adapted to your system requirements (architecture, etc):
git clone git://source.winehq.org/git/wine.git ~/wine-git
cd ~/wine-git
git checkout wine-1.5.9
wget http://dl.dropbox.com/u/6901628/raw3.patch -O ../raw3.patch
git apply ../raw3.patch
./tools/make_requests
mkdir ../wine-build
cd ../wine-build
../wine-git/configure --prefix="$HOME"
make -j3
make install
You may now want to add the new WINE to your PATH variable (export PATH="$PATH:$HOME/bin", you can also add this to your shell's startup script (eg. bashrc).
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