I've ported the prxdecrypter sample of the pspsdk to 260, that decrypts the flash modules using native functions from the firmware (sceKernelCheckExecFile)
According to my tests on an emulated 2.50, it should work, but not tested in a real firmware.
Anyways, this release is hard-coded for 2.60 only, not for 2.50
- Init prxdecrypter in GTA
- The memstick will flash for a while.
- When it finishes to flash, restart the psp.
- Connect the usb and you'll see (hopefully) the decrypted files in "ms0:/kd" and "ms0:/vsh/module"
UPDATE: It's confirmed that it decrypted most prx's, but some prx's didn't decrypt and some are invalid, i don't know why.