Note: I just updated to the update released December 10th for the droid and was able to reapply the update.zip.
The instructions are here
- Download this file and rename it update.zip on the sdcard.
- turn off the phone
- turn on the phone holding down the x key on the keyboard
- When you see the Motorola symbol, press Vol+ and Camera buttons together.
- An onscreen menu will appear, use the d-pad to navigate to update.zip and type return to apply
- After the phone reboots, Go to Settings -> Applications -> Development and enable USB Debugging
- Connect the droid to your desktop, download the sdk
- unpack the sdk and navigate to tools directory
- as root/administrator run adb start-server
- next run adb shell
- su to root /system/bin/su
- remount the root filesystem rw
I don't know if the device will always be the same (/dev/block/mtdblock4), best to check first.# mount rootfs / rootfs ro 0 0 tmpfs /dev tmpfs rw,mode=755 0 0 devpts /dev/pts devpts rw,mode=600 0 0 proc /proc proc rw 0 0 sysfs /sys sysfs rw 0 0 tmpfs /sqlite_stmt_journals tmpfs rw,size=4096k 0 0 none /dev/cpuctl cgroup rw,cpu 0 0 /dev/block/mtdblock4 /system yaffs2 ro 0 0 /dev/block/mtdblock6 /data yaffs2 rw,nosuid,nodev 0 0 /dev/block/mtdblock5 /cache yaffs2 rw,nosuid,nodev 0 0 /dev/block/mtdblock0 /config yaffs2 ro 0 0 /dev/block//vold/179:1 /sdcard vfat rw,dirsync,nosuid,nodev,noexec,uid=1000,gid=1015,fmask=0702,dmask=0702,allow_utime=0020,codepage=cp437,iocharset=iso8859-1,shortname=mixed,utf8,errors=remount-ro 0 0 # mount -o remount -o rw -t yaffs2 /dev/block/mtdblock4 /system - now make a copy of sh and call it su-something or replace su
# cd /system/bin # cat sh > su or # cat sh >su-fake # chmod 4775 su or # chmod 4775 su-fake # exit