wahhh....wahh...wah...
do you know? after searching on many many forums and tested a whole bunch of X-Terminal commands... you know? you know?...

I plug to PC again and Device memory appearred as "MyDocs"
I can't believe it, i think the PC can open it not the N900...
But no, N900 now can open Device memory again, the line "Memory Card Corrupted" is no more....

Damn damn, i just want to hug someone and jump on like a crazy kangaroo...
Now i can't remember which thread i visited (I'll post here later) but i just want to tell you, anyone have an error like mine, don't break your phone or re-sell it, just keep searching and you'll got what you want.
Thank you all