[Unattended] /dev/dsk1 to /dev/sda1

Hello,
on my target system two partition exist. sda1 (fat32, bootable) and sda2 
(ntfs, not bootable)
sda1 is the partition for the unattended setup.

First I tried to continue, when the the 'Choose partitioning 
scheme'-dialogue appeared . But without any success. Unattended told me :
-----------
mount: mounting /dev/dsk1 on /c failed: Invalid argument
-----------
Of course he can't mount /dev/dsk1 because there is only /dev/sda1 and 
/dev/sda2. But i think i cannot rename /dev/sda1 into /dev/dsk1 - or?
But although the install.pl must handle this somehow - can someone 
explain me how?
    or
Where in the scripts is the place to change /dev/dsk1 into /dev/sda1? 
(and is it that easy, as i think?)



Second i tried to run parted manually, only for experiences: I created 
to partitions like above but i get the same result

Best regards, Martin

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