Using Unix OS and ASE 11.92 and ASE 12.5

I've done a backup from ASE 11.92 and then update to ASE 12.5. Finally I did a load database from the backup (from ASE 11.9.2) to the new ASE 12.5 on the same system. I experience losing some tables. Could someone told me is this possible? Why or Why not? If it is possible then how can I correct it?