Hacking Help about 3.xx .pkg to work 4.xx cfw

[Jrel]

Hi
Is there a way that i can resign a .pkg file to work on 4.xx cfw i have try to convert one of psx classic psp eboot to a .pkg using psp2ps3 tools. but when i try to run the converted pkg it gives me the 800 error. " btw the pkg installs fine"