As it stands now (i.e. version 1.23), your script will bite the dust if you try to use both his module and the signal handlers because of "eval".
I got around this by modifying 3 of his modules (RSA.pm, Cipher.pm and Auth.pm), and making 'local' copies of the signal handlers within the appropriate subroutines (making them undef). I probably just should have done it once, in the constructor, but I was led around by the debugger and once I got it working I didn't feel like going back.
Of course, after tinkering with this nonsense for a couple of hours I thought to myself, "$self, do you think that there might be a module out there that deals with this?". Naturally, I found one (only just recently written) called Sig::PackageScoped that deals with just this situation.
As it stands it could probably be handled better than just sending ssh errors to the ether (i.e. ignoring them), since I might actually want to trap those someday as well. I've suggested this idea to Ben, and he seems to like it.