We have just posted an updated version of the Windows 2003 Cluster Management Pack. This update resolves several customer initiated issues. This update also includes some changes in order to prepare for the Windows 2008 Cluster MP.
Here is a link to the download: http://www.microsoft.com/downloads/details.aspx?FamilyId=AC7F42F5-33E9-453D-A923-171C8E1E8E55&displaylang=en&displaylang=en
Due to the nature of the changes you will need to first uninstall the previous version of the cluster management pack. The steps are documented in the MP Guide which is part of the download package. The MP guide also has a complete list of changes.