In addition to Joost's fine advice: if you really want to make sure that VAX/VMS support stays working, set up a weekly (or even daily) cron job to do a smoke test. Even if you run it inside the emulator, it's better then nothing, and AFAICS, "nothing" is exactly how much smoke testing under VMS we currently have, from the stats.
Oh, and ObTrivia: the most successful platform for perl is dec_osf, with a successful make test 89.04% of the time.
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