At one point, I forget when, there was a bug in the code to save state during
process switching which resulted in random FPE signals (I was getting reliably
hit in named).  I don't know if that affected stock 1.1, but it might have;
upgrading to 1.2 is probably the most straightforward solution, or you can
diff the assembler files and see if you can deduce which changes from 1.1
are the ones you need...