pax error on appending data to LTO3

I have problem when I use the command "pax -awvf /dev/rmt0 ./data1" in AIX 5.3.0.0. The command with parameter -a allow me to append the tape but when I try to retrieve the data that I append, it will show me error.
I would like to know if anyone have the same problem and any solution found?

Tq.