Ok problem solved. The basic trouble with the backup volume on which I wanted 
to clone was that it had it pool type set to Backup. And the volume to which I 
was trying to clone also had its pool type set to Backup. I changed the 
destination pool type to Backup Clone and re-ran the nsrclone command with 
volumeid instead of savesetid:

C:\Documents and Settings\Administrator>mminfo -avot  -q "ssid=3080968818" -r 
"volume,volid"
 volume        volid
PM0053         1503831882

C:\Documents and Settings\Administrator>nsrclone -vvv -s 1ms013 -b Test -V 
1503831882
nsrclone: Cloning the following save sets (ssid/cloneid):
        11679bd6-00000006-56a2a7d6-48a2a7d6-02ab0000-a1551ae8/1218619302
        35381434-00000006-b7a3da72-48a3da72-054a0000-a1551ae8/1218697842
        5d157641-00000006-57a2a7d6-48a2a7d6-02aa0000-a1551ae8/1218619302
        5ebf2b43-00000006-b8a3d02d-48a3d02d-05490000-a1551ae8/1218695154
        68570f64-00000006-58a2a7d6-48a2a7d6-02a90000-a1551ae8/1218619302
        e74723e7-00000006-51a2cc53-48a2cc53-02b00000-a1551ae8/1218628691
Automatically copying save sets(s) to other volume(s)

Starting cloning operation...
  ...from storage node: 1ms021
nsrclone: Successfully cloned all requested save sets
nsrclone: Clones were written to the following volume(s):
        PM0186


Thanks for your replies,
opopanax.

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