> According to the man page of st, the forth field is the options of the
> drive. For DLT7000, Sun recommends to use 0x19639, Veritas recommends to use
> 0x1D639. To my experience, both are working perfectly.

The difference appears to be that Veritas is adding the
the option `ST_BUFFERED_WRITES':

     ST_BUFFERED_WRITES
           If the  flag is set,  when data is written to the tape
           device,  the  data  is  buffered  by  the driver.  The
           application may receive acknowledgement of  completion
           of  the write request before the data has been written
           to tape.