Schuess, be careful for space character in directories!
[merge]
tool = meld
[mergetool "meld"]
prompt = false
keepBackup = false
keepTemporaries = false
path = C:/Program Files (x86)/Meld/meldMeld.exe
cmd = '\"\"/cC/Program Files (x86)/Meld/meldMeld.exe\" $PWD\"$PWD/$LOCAL$LOCAL\" $PWD\"$PWD/$BASE$BASE\" $PWD\"$PWD/$REMOTE$REMOTE\" \"--output=$PWD/$MERGED'$MERGED\"