KB941409 has been released : http://support.microsoft.com/kb/941409/en-us

This discusses and issue which has led to numerous calls to Microsoft CSS. Since the Operations Manager task subsystem relies upon the SQL Broker being enabled, any task will fail if the broker is disabled.

SYMPTOMS

When you run the Discovery Wizard in Microsoft System Center Operations Manager 2007, the wizard may stop responding (hang). This behavior typically occurs in the "Discovery Progress" section of the wizard. Additionally, the following event may be logged in the Operations Manager log:

Event Type: Information
Event Source: Health Service Modules
Event Category: None
Event ID: 11553
Date: Date
Time: Time
User: N/A
Computer: Management_server name
Description:
Computer verification summary event.
Verification successes - 2
Verification failures - 0
Verification time elapsed - 3 seconds

CAUSE

This issue may occur if Microsoft SQL Server Service Broker is not running on the management server.

RESOLUTION

To resolve this issue, enable SQL Server Service Broker. To do this, follow these steps:

1.
Start SQL Server Management Studio.

2.
Click New Query.

3.
In the navigation pane, expand Databases, and then click OperationsManager.

4.
In the details pane, type the following command, and then click Execute:

SELECT is_broker_enabled FROM sys.databases WHERE name = 'OperationsManager'

5.
In the results that are displayed, verify the value that is displayed in the is_broker_enabled field. SQL Server Service Broker is disabled if this value is 0 (zero).

6.
In the details pane, type the following command, and then click Execute:

ALTER DATABASE OperationsManager SET ENABLE_BROKER

SQL Server Service Broker is now enabled.

7.
Close all open windows and dialog boxes.

8.
Test the Discovery Wizard in System Center Operations Manager 2007.

MORE INFORMATION

System Center Operations Manager 2007 depends on SQL Server Service Broker to implement all task operations. If SQL Server Service Broker is disabled, all task operations will be affected. The resulting behavior may vary according to the task that has been initiated. Therefore, it is important to check the state of SQL Server Service Broker whenever unexpected behavior is observed around a task in System Center Operations Manager 2007.