What's kind of sad is that anyone knowledgable about crytology and the ECDSA algorithim used by Sony should've noticed immediately that their implementation wasn't working right. The parameters, R, n, K, and Da, geohot gives in the link above are what you need to your own signing. The "n" parameter is a constant based on the ecliptic curve used and doesn't need to be a secret. The "K" parameter is the now infamous random number that should've changed everytime something was signed. "Da" is the private key that's supposed to be kept secret but was easily discovered because "K" never changed.
"R" however, is part of the signature. It's not supposed to be a secret, it's used to verify the executable (or whatever) was actually signed by Sony, not any one else, and not modified in anyway. It's also not supposed to be a constant, each signature should have its own unique "R" value, but becase "K" never changes, neither does "R". Just by looking at the signatures their implentation generated, and seeing how half the signature is always the same, they could've seen that something was wrong. Ironically if they hadn't gone to the additional and unnecessary step of encrypting the signature in the executable it would've been blindingly obvious even to third-party developers who knew little about cryptology. This could've been caught and fixed before the PlayStation 3 was ever released to the public, if Sony had just been dumb and not also stupidly paranoid.
The prahase "Epic Fail" gets way over used, but this time...
(As for the rest of the constants, the "pub" parameter is probably Sony's now uninteresting ECDSA public key. "erk" and "riv" are the secret parameters of the AES encryption method used to encrypt executables.)