Creating a ParseProjectContent instance

Hi,

I'm using a couple of ISharpDevelop libraries for my Web based editor. Right now I'm working on adding references to a project so that Intellisense works properly for external references. I managed to add assembly references like this:

var referencedContent = _projectContentRegistry.GetProjectContentForReference(assemblyReference.Name, fileName);
projectContent.AddReferencedContent(referencedContent);	

Where _projectContentRegistry is an instance of the ICSharpCode.SharpDevelop.Dom.ProjectContentRegistry class. However, I can't figure out how to add a reference to another project in the solution. How do I do that?

Thanks

artem