Checksums aren't unique; eventually, you find two strings that differ but have the same checksum. Checksums are merely a precautionary measure.
Jeff japhy Pinyan,
P.L., P.M., P.O.D, X.S.:
Perl,
regex,
and perlhacker How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart