It would been nice if you would post your code... Here's what my theory is (w/o seeing any code):

1. When you use capital "S" it's not finding the Strict module because it doesn't exist. It's named "strict.pm" NOT "Strict.pm"
2. Your code has things (or the lack therof) in it that strict doesn't like: e.g. undefined varibales etc. The reason why you're getting errors (you didn't post what your errors were either!) when you spell it correctly is because _it_is_ finding the strict.pm module.

Joshua

Update: Fixed a couple typos.
Update 2: um, the Strict module _has_to_ exist otherwise you'll get errors. my bad :)