mysql主从库同步问题
错误日志如下：

120731 3:11:43 [ERROR] Slave SQL: Error 'Lock wait timeout exceeded; try restarting transaction' on query. Default database: 'device'. Query: 'UPDATE device SET 
`lastip`='114.249.37.221' where `did`='2zkql5ha89v10k6c'', Error_code: 1205

120731 3:11:43 [Note] Slave SQL thread exiting, replication stopped in log 'log-bin.000756' at position 48995881
120801 9:29:14 [Note] Slave SQL thread initialized, starting replication in log 'log-bin.000756' at position 48995881, relay log './mysql-relay-bin.001903' position: 48996024



像这样的问题需要怎么解决，之前我使用的办法是将innodb_lock_wait_timeout设置成100，可是第二次还是出现同样的问题

------解决方案--------------------
用的是myisam表引擎？
------解决方案--------------------
`did`='2zkql5ha89v10k6c没有索引吗