In reply to:
it's a secret :)
Unless you intend to resell your hosting and want to 'brand' the panel so your clients don't know they are ultimately hosted by DreamHost, I would forget all about cPanel. As rlparker said; The custom DreamHost panel is superior to cPanel in almost every way.
Honestly, if the lack of this branding ability really bothers you, then you may be better off looking elsewhere for your hosting. There are hosting companies that specialize in reseller accounts, but DreamHost is not one of them.
Of-course, if you go elsewhere, you will be missing out on perhaps the best value hosting packages available. 
Mark
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