While both of you said sane things, we're now diverging from the original answer. If we start giving advice along these lines, we're way more advanced, and giving advice about portable programming and Module-Quality (through testing).

Modules should not only be tested on as many as possible OS's (and versions thereof), but also on as many versions of supported perl versions, threaded and unthreaded, 32bit and 64bit, with or without longdouble and with or without DEBUGGING.