It\'s very easy to screw qpe.sh up and if you do then qtopia wont boot nad you can\'t do anything with your Z till you fix it!
You have 2 options
1) Easy option - reflash ROM or use the Erase (format) option to return your Z back to factory settings.
Remove battery, replace battery and power on while holding OK key.
Choose 3rd option to reformat filesystem or 4th option to flash new rom. NOTE this will erase any settings you hace configured
2) Harder Option - boot into single mode, mount the mtdblock device containing qpe.sh and copy the backup qpe.sh.
The hard part is booting into single user mode. Remove battery and ac adapter, wait about a minute, replace battery and while holding down D and B keys switch the battery lock to locked position. If the zaurus doesn\'t boot to console mode after about 15 secs try hitting the power button while keeping the D and B keys depressed. If it boots normally - repeat above procedure till lyou get console mode. This generally takes me 3 or 4 tries till I get single user mode. You then have to mount the /dev/mtdblock1 or /dev/mtdblock2 devices (mount -t jffs2 /dev/mtdblock1 /mnt/tmp). From memory /dev/mtdblock1 is the / filesytem while /dev/mtdblock2 is the /home filesystem, you probably want the /dev/mtdblock2 system.
WARNING you can screw up the filesystem here if you aren\'t sure of linux commands - if you are worried then you are better off using the first option.
Stu