IMPLEMENTS: http://code.google.com/p/zfdatagrid/issues/detail?id=495
IMPLEMENTS: http://code.google.com/p/zfdatagrid/issues/detail?id=495

zervel/grid,zfdatagrid/grid,zervel/grid,zervel/grid,zfdatagrid/grid,zfdatagrid/grid,zfdatagrid/grid