namespace quota not take effect

[W.H]

hi guys 
  I am testing the hbase  namespace quota at the maxTables and 
maxRegions.Followed the guide  i add the option  "hbase.quota.enabled" with 
value "true" in the hbase-site.xml .And then created the namespace :
   hbase(main):003:0> describe_namespace 'ns1'
   DESCRIPTION
  {NAME => 'ns1', maxregions => '2', maxtables => '1'}
 
  In the table definition a limited the maxtables as 1 ,but i created 5 tables 
under the namespace "ns1".It seems the quota  did't take effect .
  The hbase cluster was restarted after  hbase-site.xml modified.And my hbase 
version is 1.1.2.2.4.
  Any ideas ?Thanks .



 Best wishes.
 who.cat