All the gringos in the world better watch out too!
This was bound to happen sooner or later though, M$ has been trying for years to get a solid grip on something to do with Linux, but being so ethereal and nonentitic as Linux is, it has been hard for them. (how can you sue a company that doesn't actually exist?)
So you can imagine the day when some press monitor guy leapt up from his chair, knocking his tray of sedatives to the floor and ambled along the corridor wiping the drool from his mouth. "Lord Gates!, Lord Gates!" i can almost hear him cry, "At last, Master, we can sue those dastardly Linux mongrels!" As he stood there, panting with excitement, i can imagine Gates slowly, but slowly, swivelling in his padded armchair with that evil/dopey grin on his face "Excellent." he would have said, "Release the hounds!"
BTW, wasn't XWindows actually called "X" and NOT "XWindows"? I thought it was called X because it was an upgrade from its parent program which was called "W". The name "XWindows" was attributed to it later as, sadly, people thought of windows whenever they saw any GUI.