You should browse the perluniinto, perlunicode and encode man pages for v5.8 -- these are very instructive. (It was very good that you mentioned which version you're using, because there are important new things in 5.8.)

When you mention deleting lines, you're talking about lines in some text data file, rather than lines in a .pm file, right? I mean, why delete lines of code rather than fix them -- or do I misunderstand the nature of your .pm file?

Anyway, read up on "use utf8" and "no utf8", to see if that is instructive. Does your code deal with unicode characters? With other character sets that go beyond ASCII? (Do you use accented Latin1 characters in your variable names?)