unable to modify jffs2

Xavier DEBREUIL
2001-06-12T15:15:28Z

I have managed to mount the jffs2 ;
however, it seems that I cannot erase anything or write anything on it

/mnt/jffs2/jffs2_1/bin # df
Filesystem 1k-blocks Used Available Use% Mounted on
/dev/ram0 3963 2997 966 76% /
/dev/ram1 2011 13 1998 1% /mnt/ramdisk/rd1
/dev/mtdblock1 2048 2048 0 100%
/mnt/jffs2/jffs2_1

/mnt/jffs2/jffs2_1/bin # mount
/dev/ram0 on / type ext2 (rw)
none on /proc type proc (rw)
none on /dev/pts type devpts (rw)
/dev/ram1 on /mnt/ramdisk/rd1 type ext2 (rw)
/dev/mtdblock1 on /mnt/jffs2/jffs2_1 type jffs2 (rw)

I can list, chroot and execute things on the filesystem but no
erasure...
Is there an option I've missed ?

Xavier