First of all, you might want to try and use diagnostics (and strict as always).

Second, which of those lines are line 15? This is the kind of error you get when you declare a variable and then uses another, usually because of a typo. I see that you declare $user - do you by any chance try to login with $username but it should be $user? In you example, it should probably warn on line 6, that main::user is only used once - so this isn't the exact code that produces the error, is it?

UPDATE: And there it was. The line I was missing. :)

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