thanks zephyroth!

however, i've not got through yet.

when i was in step 6,

chown -R root:wheel /Users/admin/Desktop/Extensions/applenforceata.kext

it says that operation not permitted, can i use sudo -s and then execute the fixing the permissions' command?

and the other thing is that where do i put the new Extensions.mkext? just under the root of the lerpard dvd (together with install mac osx and mach_kernel)?

thanks again!