Oh, I see you don't have bootmenu installed so you boot everytime from flash. Well if one has problems and decides to reflash, there is possibility (with linux flasher) to reflash only rootfs keeping initfs with bootmenu intact. Now the easiest is to copy created initfs.bootmenu.jffs2 to PC and reflash just initfs via linux flasher. But I'd suggest reflashing rootfs or whole device. The glibc error does not seem like the system on device is OK.

Or if initfs on N800 is in fact writable and not full, you can do the same thing as the initfs flasher does when preparing the image. Extract proper bootmenu data for initfs (to initfs directly)
# tar zxvf initfs.oss.RX-34.2006.51.tgz -C /mnt/initfs
then copy over the bootmenu.sh
# cp bootmenu.sh /mnt/initfs/
and bootmenu is installed :-) This is not possible on n770.