The guy behind PSARDumper v0.1, PspPet, released today v0.2 at PS2Dev.org:
http://forums.ps2dev.org/viewtopic....c14d0eea2b7d3cf

Here is what he said about it:

"You will need a homebrew compatible PSP (1.0 or 1.50 firmware)
The new PsarDumper2 is very similar to the old "PSAR Dumper" release, but it now does the things the old version can't handle.

This new version will decrypt the 2.0 PRXs!!! (and put them in the OUTX folder)

Advanced expert tool.
A tool to help legal reverse engineering of the PSP system components.
Extracts the contents of the update data file, and saves them as separate files on memory stick.
NOTE: The non-decrypted PRX files are not saved in this version so it will fit on a 32MB memory stick.

Legal Note:
The files you download (ie. the updater EBOOT.PBP) and the files extracted by this tool (ie. the contents of the OUT and OUTX folders) are all Sony copyrighted material !!
You can use them under certain "fair uses". Do not post these files on the Internet. Use this tool at your own risk! The tool itself contains no Sony copyrighted material.

NOTE: you can load 2.0 decrypted prx files on top of the PSP 1.0/1.50 system, but system incompatibilities make things very difficult. This is what a lot of people want. This is only a step along the path (but a big step in the right direction)."

Download it here: http://aibohack.com/psp/psardump02.zip

Have a nice day!