For those who are familiar with Vanitygen, the command line switch you need for Dopecoin is -X 8  

For those less familiar, I posted a quick guide here: http://www.reddit.com/r/DopeCoin/comments/1y5agy/tip_using_vanitygen_with_dopecoin_for_cold/

You too can have a customized address prefix for your Dopecoins
4TwentyFG4xEDPwKrCg69sJ75vmijYb2m2