How to build a project containing Reporting Service project

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Solution file warning MSB4122: Scanning project dependencies for project "TestProject\TestProject.rptproj" failed. The default XML namespace of the project must be the MSBuild XML namespace. If the project is authored in the MSBuild 2003 format, please add xmlns="http://schemas.microsoft.com/developer/msbuild/2003" to the element. If the project has been authored in the old 1.0 or 1.2 format, please convert it to MSBuild 2003 format.