Source control error when working with MCMS project

When we try to source control our MCMS project to TFS we are able to get the files and structure pushed to the system However, when we try to check in the project we are receiving the following error:

Unable to cast object of type 'Microsoft.ContentManagement.DeveloperTools.VisualStudio.Documents.TemplateExplorerDocument' to type 'Microsoft.VisualStudio.Shell.Interop.IVsHierarchy'.

Any ideas or solutions?

Thanks

Marc

[776 byte] By [MarcRush] at [2007-12-20]