If choosecat is really in its own package, and it's a different package from login, you shouldn't have any trouble. The different packages provide different namespaces, so Perl will know the subs are different. If neither declares a package, they'll both run in main, in which case something like &choosecat::load; won't work, since there's no such package as choosecat.

If both run in package main, you can work around this by temporarily creating a new package, then loading in choosecat.cgi in that package:

  eval {
    package choosecat;
    require "choosecat.cgi";
    &choosecat::test;
  };
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That said, I agree with the other posters that refactoring your code so that functions needed by more than one program are in a seperate library is probably what you really want to do.