SQL Lock Rules
These Rules monitor the number of locks being held by the SQL Server. Both exclusive only or all locks can be monitored.
SQL-DMO library must be installed on the monitoring engine. It is generally installed as part of SQL Server client package, but do check sqldmo.dll is in drive:\Program Files\Microsoft SQL Server\80\Tools\Binn
You can use this Rule to monitor the number of locks to either the whole of the SQL Server on the machine, or to an individual database.