If you've written your file on a Windows system and ftp'd it to a Unix system in binary mode, the line endings wouldn't be converted properly. perldiag on your machine might have more information -- on mine, it suggests the error message might be "Illegal character %s (carriage return)".

If you can open the file in vi, you might try the command ":set ff=unix". Or see Remove the ^M Character from a Document.