I have installed Crypt-DES successfully from University of Winnipeg. This is one of the best places to get active state ppm modules.

Here is the information on the package.

ppm> describe 1
====================
Package 1:
    Name: Crypt-DES
 Version: 2.03
  Author: Dave Paris <a-mused@pobox.com>
   Title: Crypt-DES
Abstract: Perl DES encryption module
Location: UWinnipeg
Available Platforms:
       1. MSWin32-x86-multi-thread-5.8
====================
[download]

And here is the information on the repository. You will notice that I have this location as the number 1 place to look. :-)

ppm> rep describe 1
Describing Active Repository 1:
    Name: UWinnipeg
Location: http://theoryx5.uwinnipeg.ca/cgi-bin/ppmserver?urn:/PPMServe
+r58
    Type: PPMServer 2.0
ppm>
[download]

Another location is our own crazyinsomniac's repository (though they do not seem to have this one). Check out crazyinsomniac for more details.