I know several other Monks will jump on this, too, but here's my answer. :)

#!/usr/bin/perl -w

use strict;

my $date = '11/29/2001';

print "DATE (before): $date\n";

$date =~ s/\//\\\//g;

print "DATE (after): $date\n";
[download]

Output:
$ ./slash.pl
DATE (before): 11/29/2001
DATE (after): 11\/29\/2001

Jason