Not wanting to unfairly assign any blame this time, let me just say that when I disable Norton Anti Virus Perl seems to work fine and leave it at that.
You've hit the nail on the head here with the Norton AntiVirus. I had no end of troubles with real-time virus protection when attempting to run scripts containing backticks, or trying to compile code. I fired off a message to Norton, and they replied that "developers are encouraged to disable virus protection before compiling programs."
As long as you remember to have the realtime protection disabled every time you run a script or compile software, and turn it back on when you've finished (how ludicrous is that?) you'll be fine...
ryddler