I believe the IBM drivers that has that feature start with 6.1.6.2 and 
higher, that is if you have IBM tapes , the drivers are available on IBM 
site.
Also if you like to check if drives are sequenced or not, usually, slow 
label failure should give you a clue along with nsrjb -HEvvv ( No backup 
actively should be present) failing.
HTH

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