thanks santa but i dont have a clue about partitions etc.
i cant get my usb stick to work now here is the output from telnet
[SifTeam]$ cd /tmp

[SifTeam]$ mount #

rootfs on / type rootfs (rw)

/dev/root on / type squashfs (ro)

none on /tmp type tmpfs (rw)

none on /dev type tmpfs (rw)

none on /mnt type tmpfs (rw)

/dev/mtdblock4 on /var type jffs2 (rw)

none on /tmp/mqueue type mqueue (rw)

proc on /proc type proc (rw)

sysfs on /sys type sysfs (rw)

devpts on /dev/pts type devpts (rw)

tmpfs on /dev/shm type tmpfs (rw)

usbfs on /proc/bus/usb type usbfs (rw)

[SifTeam]$ umount /dev/sda1

umount: can't umount /dev/sda1: Invalid argument

[SifTeam]$