Hey guys. 30 minutes after I posted, an idea just pop into my mind and it worked, so i just post this here for anyone who encountered the same problem.
Dont change the eboot or param sfo, just rename the 2 update folder in hdd\game (u know, the place where it usually contain the update) to anhything so the game will change it back to the original verson (which the eboot and param still work), play the game thourgh that part, save exit and rename the 2 folder again,voahla ^^
Tks all.