While the exact way it could happen is unclear (and whether or not it is at all possible is subject of debate) it would be analog to the way Special Relativity violates Newton's mechanics: it covers special cases that demanded new models that explain them.
SR is not a law (as Newton's laws are not "laws" in the strict sense) but a model we use to explain certain phenomena.
So, it would violate SR under certain conditions (just as SR/QM violate newtonian mechanics under certain conditions?).
Boy, we really need a unified field theory to work out the kinks in physics ... I guess this could be a chance for String theory to provide a falsifiable prediction that differs from relativity and quantum physics.
Don't worry. We will find ways to violate any unified theory we can come up with ;-)
We have to agree experiments that could falsify String Theory are long overdue. If ST physicists can't come up with something, people will start calling it "String Hypothesis".
SR is not a law (as Newton's laws are not "laws" in the strict sense) but a model we use to explain certain phenomena.