I am experiencing a strange problem with Mathematica 3.0 for Linux. I have tried both the Accelerate X server and the Xfree86 servers, and they produce the same symptoms. When I attempt to incorrectly complete the brace structures, the program segfaults. For example typing the characters ''[}'', yes, a square left bracket followed by a right brace, will give a segfault. This doesn't happen on the Windows versions, and I expect this has a solution which I have overlooked, typos do happen.