From bitgamer thread, posted by "Tweakster" and he posted originally from.. I dont know xD.
The tools I'm using are these: http://www.mediafire.com/?qvvd5febj6292nw, the original rar came with an .exe file that was blocked by NOD, and you never get to use it anyways, so most likely a viirii, rest are the actual tools you need to use, hope it helps, you get the hang after 3-5 resigns.
I just updated from 3.55 kmeaw to Rogero 4.21 v1.09 (Final) and had a Whole Bunch of both PSOne PSN Games And PSN Retail Games like Beyond Good and Evil HD, Sonic The Hedgehog Episode 1,Xmen Arcade etc still installed....
I had to Reinstall the crack/fix.pkg's for the PSone PSN Games to Run again,
but the Retail PSN Games mainly duplex's 3.55 PSN Games with fixes gave me a 8000xxxxxxxx Error. Because I did not want to lose all my psn games since updating to 4.21 cfw I managed to may them work
You will need
2. 4.21 EBOOT Resigner
3. PKG ContentID
Here is the fix for 4.21 cfw part
1. Run PkgView_1.3 ON your PC Drag the game crack.pkg into the program, right click on the folder and press extract to source folder.
(Note: Must be the crack/fix pkg (usually smallest pkg file size) this is the pkg that will fix the PSN games for the 4.21 cfw)
2. After the Package has Extracted find the Eboot.bin in the USRDIR Copy it over to the 4.21 EBOOT Resigner Folder
3. launch the 4.21 EBOOT Resigner, press 2 On Keyboard then enter than enter again
4. You will be asked to enter the content-id of the application
5. Open pkg ContentID Program, load the pkg, once you do you will see your Content-ID , copy it then go back into the 4.21 EBOOT Resigner program and paste the Content-ID and hit enter,
(example TMNT Turtles In Time ReShelled ContentID is SET043-NPUB30107_00-TMNTRESHELLED001)
6. Once the 4.21 Eboot Resigner is done copy/paste the new eboot.bin back into the extracted crack/fix usrdir folder and replace the eboot.bin with the new one.
then move the extracted pkg folder into the psn_package_npdrm folder
7. Go to the psn_package_npdrm folder open the package.config file in notpad (if there is not one make a new text document and rename it to package.config
it should look like this except for the content-id you will need your Content-ID of the game your editing currently from the pkg ContentID Program you obtained earlier in step 5
Content-ID = 00000000000000
K_licensee = 0x00000000000000000000000000000000
DRMType = Free
ContentType = GameExec
PackageType = HDDGamePatch
PackageVersion = 01.00
8. save the package.config close it
9. hold shift on keyboard and right click on mouse anywhere in the psn_package_npdrm folder select open command window here.
10. A cmd window will open copy and paste
psn_package_npdrm.exe package.conf BLND00001
(Note: where BLES01467 is the id of your game example NPUB30107)
11. hit enter and psn_package_npdrm should make a new pkg with the resigned eboot.bin
12. install game pkg's in this order
3. the .pkg you just created
if everything went right your 3.55 psn game now runs on 4.21 cfw with no 8000xxxxxxxx errors
So far as long you have an update file you can sign anything as long is from PSN.