how does TSM / sql backtrack use management classes?

[Reichmuth, Michael R.]

We're using SQL backtrack to backup our oracle database. If two backtrack
backup scripts are run using two different management classes against the
same database, (ie.. management class one has 3 version, 30 days and
management class two has 6 versions 60 days) how does TSM handle the backup?
Will it in effect use the shortest management class. Or will it keep two
sets of the database, one for 3/30 and the other for 6/60?