VACUUM problems with 7.4

I am sure there is no transaction open with the table banner_stats2.
Still VACUUM FULL does not seems to effective in removing the
dead rows.

Can any one please help?

Regds
mallah

tradein_clients=# VACUUM FULL verbose banner_stats2 ;
INFO: vacuuming "public.banner_stats2"
INFO: "banner_stats2": found 0 removable, 741912 nonremovable row versions in
6710 pages
DETAIL: 737900 dead row versions cannot be removed yet.
Nonremovable row versions range from 61 to 72 bytes long.
There were 120 unused item pointers.
Total free space (including removable row versions) is 246672 bytes.
0 pages are or will become empty, including 0 at the end of the table.
557 pages containing 61344 free bytes are potential move destinations.
CPU 0.15s/1.23u sec elapsed 1.38 sec.
INFO: index "banner_stats_pkey" now contains 741912 row versions in 2173
pages
DETAIL: 0 index row versions were removed.
0 index pages have been deleted, 0 are currently reusable.
CPU 0.03s/0.05u sec elapsed 0.09 sec.
INFO: "banner_stats2": moved 0 row versions, truncated 6710 to 6710 pages
DETAIL: CPU 0.00s/0.00u sec elapsed 0.00 sec.
VACUUM
tradein_clients=#