[Yaffs] mout problem with yaffs

Hi all,

I am getting the mount problem with yaffs2, i can successfully mount a Nand block device as yaffs2 format, write some files to it, edit, save , review and every thing is ok. But the problem comes when i reboot the system or unmount/mount again, the whole data that i wrote before was lost.
I am using the lastest version of yaffs2 from cvs.
Any one experience with this prolem ? what is wrong with me ?
Pls advise !

Thanks
Tung