I have a good deal of perl programs run from crontab. The only special treatment I have needed in some cases is properly setting the PERLLIB or PERL5LIB environment variables. In those cases, because crontab entries are usually executed using /bin/sh, you can do something like this:

0,30 * * * * PERLLIB=path1:path2 /your/perl/program.pl
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--ZZamboni