There's a group of so-called 'developers' on Maxconsole (maybe just one kid, I don't know for sure) who 'released' a custom firmware today called 3.40 PE-A.
Here's all you need to know about it.
The 'release' came as a dump of flash0, meaning that not only is it illegal, but it contained files that were modified upon installation so they'd only work on that PSP. This is called 'sigchecking' and it has been present in every firmware from 2.80 to the current ones.Originally Posted by me
Avoid this firmware unless you enjoy bricking your PSP.