Is Crypt::Lite a joke? It seems to be simple-XOR implemented in the stupidest way possible.

substr($a, $j, 1) += substr($b, $i, 1);
substr($a, $j, 1) = 0 if substr($a, $j, 1) == 2;
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Also, it looks like the secret key is stored in the encrypted message as a message integrity check. Absolutely stunning.

Verdict: DO NOT USE THIS MODULE. You would be better off with no encryption at all, because that way at least you won't have a false sense of security.