Not knowing that much about Linux I would probably have something that sits in a loop grabbing the output from the uptime command .. if the load numbers at the end of the line (it's the number of processes waiting, not CPU load, I know) gets into the red zone, fire off an E-Mail using Mail::Sendmail. Have it sleep for 60 seconds after each run, perhaps wait until you have three to five successive red zone numbers.

--t. alex
but my friends call me T.