When building solutions outside Visual Studio 2010 that contain both a pipeline project and a pipeline components project, building may fail.
As it seems, determining the buildorder for the components seems to be inclusive, leading for some solutions to fail with the message that references to the pipeline components cannot be resolved.
Cause for this is the fact that the reference is always to the GAC, not to a project. Somehow Visual Studio 'knows' this and acts accordingly, and when using MSBUILS this might fail. I say might, as we have solutions that do build consistently aswell as solutions that do fail consistently.
In order to 'fix' this, you have to manualy set your projects dependency.
In Visual Studio, right-click the solution and select Properties.
On the propertyscreen select Project Dependencies
There, select your Pipeline project and check the dependency with the Pipeline component.
Klik Apply, then save the solution.