The irony is that Watch Dog works some of the time - else you would not get the mails saying that it was failing occaisionally. I think you need to start debugging this by looking to see if you can make the perl scrip fail from the command line. Try logging in as your aolserver user and running /web/$server/bin/aolserver-errors.pl and see if you can get it to error - hopefully informatively this time. "interupted system call" could be the call to the perl script - or a call within it. I can't really tell in absence of a system to play with myself.
