It works fine for me. I changed the char classes to \d, but that doesn't change anything. I backslashed the '.' so it matches a literal '.' and not any character. Perhaps your string has whitespace around it that you're not expecting? 
/^\s*\$?(\d{1,3},(\d{3},)*\d{3}|\d+)(\.\d\d)?\s*$/

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Try that...
Jeff japhy Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and perl hacker
How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart

In reply to Re: Regular Expression Currency Check by japhy
in thread Regular Expression Currency Check by Anonymous Monk

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