The reason is that $file =~ s/\s*$// is clearing the $DIGIT variables and setting its own (which happen to be undef, since they're not defined by the regex). Perhaps you want to take this approach:

if (my ($f, $l) = $line =~ /(.+)\s*\(\)\xA1\s*(.+\.txt)/) {
  $f =~ s/\s+$//;  # notice \s+ and not \s*, too
  print OUT qq{<a href="$l">$f</a><br>\n};
}
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_____________________________________________________
Jeff[japhy]Pinyan: Perl, regex, and perl hacker.
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