Nubuild in VS 2010 - Why is it looking into "obj\Debug\..."? The artifacts for the Schema project are generated into "bin\Debug\..."

[inehme]

I am using Nubuild in VS 2010. I added a new NuGet Package project to the solution and added a reference to a TFS.Testing.BizTalk.TestApp1.Schema project. When I build the Nuget package to get the error: Could not copy the file "obj\Debug\TFS.Testing.BizTalk.TestApp1.Schema.dll" because it was not found. Why is it looking into "obj\Debug..."? The artifacts for the Schema project are generated into "bin\Debug..."