The iptables quota match has not been updated to reflect the new xtables
location/structures in 2.6.18-rc.  In addition, it has a bug which makes
it impossible to delete a rule once added.  E.g.:

# iptables -A foo -m quota --quota 1111 -j RETURN
# iptables -D foo -m quota --quota 1111 -j RETURN
iptables: Bad rule (does a matching rule exist in that chain?)

Below patch fixes both issues and resolve bugzilla #496.

Phil