Welcome to the MSBuild tasks for WSS 3. These tasks are designed to help automate SharePoint operations with MSBuild projects. The tasks rely on the SharePoint Object Model and for that reason, the tasks need to be executed on a WSS 3 server. Also note that at this stage, they are designed for MSBuild v2.0.
MSBuild Reference: http://msdn2.microsoft.com/en-us/library/0k6kkbsd.aspx
Windows SharePoint Services Development Center: http://msdn2.microsoft.com/en-us/sharepoint/default.aspx
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