One more update for the jas0nuk's PRXdecrypter.
Download2.4a --> 2.4b
- Decryption error for an old key, tag 0x4C940AF0, fixed.
- Decryption key added for pops_04g.prx from 6.XX firmwares - tag 0x457B1EF0
- Slightly more information when encryption is likely to fail (SHA-1 check warning)
- NOTE: key for tag 0x2E5E10F0 does not appear to be working due to a new encryption method. I'll look into it.
- New EBOOT.BIN key added for tag 0x2E5E12F0. As above, might not work.