I had a day off today, and this problem bugged me until I did something about it. So here is a solution: 
use Math::Fleximal;
print Math::Fleximal->new(
  "2dd9f2ba1f924996fa231fdceb4c6f57",
  [0..9, 'a'..'f']
)->change_flex([0..9,'a'..'z','A'..'Z'])->to_str();

[download]
which will print "+1owfX3qQrJC5h1IIWhMy23". Strip off the + and you are in business.

You will need Math::Fleximal of course.

In reply to Re (tilly) 1: Compact MD5 representation by tilly
in thread Compact MD5 representation by jplindstrom

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