Assertion in restore_backup_open_tables_state on concurrent HANDLER

When executing a RQG workload with concurrent HANDLER, maria-5.3-handler asserted as follows:

mysqld: sql_class.cc:3340: void THD::restore_backup_open_tables_state(Open_tables_state*): Assertion `open_tables == 0 && temporary_tables == 0 && handler_tables == 0 && derived_tables == 0 && lock == 0 && locked_tables == 0 && prelocked_mode == NON_PRELOCKED && m_reprepare_observer == __null' failed.

backtrace:

# 2011-01-14T10:29:33 #8 0x00399d98 in __assert_fail () from /lib/libc.so.6
# 2011-01-14T10:29:33 #9 0x082727a0 in THD::restore_backup_open_tables_state (this=0xac51c90, backup=0x955b6bc0) at sql_class.cc:3340
# 2011-01-14T10:29:33 #10 0x082f3c53 in open_performance_schema_table (thd=0xac51c90, one_table=0x955b69c0, backup=0x955b6bc0) at sql_base.cc:9364
# 2011-01-14T10:29:33 #11 0x08358020 in Log_to_csv_event_handler::log_general (this=0xaaf1ba0, thd=0xac51c90, event_time=1294993584,
# 2011-01-14T10:29:33 user_host=0x955b6c7e "root[root] @ localhost [127.0.0.1]", user_host_len=34, thread_id=10, command_type=0x88582cd "Query", command_type_len=5,
# 2011-01-14T10:29:33 sql_text=0xac68da0 "EXECUTE h_r", sql_text_len=11, client_cs=0x8a93a60) at log.cc:409
# 2011-01-14T10:29:33 #12 0x083599b6 in LOGGER::general_log_write (this=0x8a9c3e0, thd=0xac51c90, command=COM_QUERY, query=0xac68da0 "EXECUTE h_r", query_length=11) at log.cc:1091
# 2011-01-14T10:29:33 #13 0x0836282d in general_log_write (thd=0xac51c90, command=COM_QUERY, query=0xac68da0 "EXECUTE h_r", query_length=11) at log.cc:4592
# 2011-01-14T10:29:33 #14 0x0829504f in dispatch_command (command=COM_QUERY, thd=0xac51c90, packet=0xac53c99 " EXECUTE h_r ", packet_length=13) at sql_parse.cc:1201
# 2011-01-14T10:29:33 #15 0x082945b4 in do_command (thd=0xac51c90) at sql_parse.cc:904
# 2011-01-14T10:29:33 #16 0x08291692 in handle_one_connection (arg=0xac51c90) at sql_connect.cc:1154
# 2011-01-14T10:29:33 #17 0x00821919 in start_thread () from /lib/libpthread.so.0
# 2011-01-14T10:29:33 #18 0x00453cce in clone () from /lib/libc.so.6