dsbk error: unable to open log file!

hi, everyone!

When I use the dsbk utility to restore data , "unable to open log file " error happened!
I created the log file /data/bak/restore.log by "touch' and lived it whith the bak data files in the same directory( /data/bak/).

I don't know what i have missed...

ndsd.log :

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Command line restore -f /data/bak/20120724.bak 20120724.bak.00001 -l /data/bak/restore.log -e XXXXXX
Processing command line
Error!: -2
Unable to open log file!
Completion time 00:00:00
1 Error!
DSBK error! -2

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