LiveCD doesn’t find persistent file

["os.news@gmx.de" <os.news@gmx.de>]

I made a persistent file as described in the manual:

dd if=/dev/null of=live-rw bs=10M seek=1
/sbin/mkfs.ext2 -F live-rw

I put this file into the root directory of an USB stick (/dev/sdb1 with vfat).

Then I started my LiveCD with the boot option: “live persistent” and – as a second try – with the boot option: “live persistent persistent-path=/dev/sdb1”. But in all cases the persistent file wasn’t recognized. Then I put the file to my internal harddrive but I had no success too. For your information, I use Debian Lenny. 

Please can you help me?

Thank you very much,
Oliver

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