It is strongly recommended to update to 2.2.2.Final due bug and security fixes if you would like to keep all 2.0.x features you use with 2.0.2.SP1.
Seam 2.2.2.Final works on AS 7.1.x too with small glitches, but these could be done.
Btw, Seam 2 is formally dead, there is no development and maintenance now. The supported Seam 2 in Red Hat products still get some sort of support but it will end soon too. Just saying a warning