IVsUIHierarchy in managed code

I'm working on a managed custom project type (in c#) with VSIP.
I must have my package to work with VS2003 and VS2005.

Right now, my package works well in VS2005 (beta2) but in VS2003, I have a few problems with the Project Properties window.
In a few places, I have read that I must implement a COM wrapper for my IVsUIHierarchy (or IVsHierarchy).

Unfortunately, I don't know how to do this.
Would someone be able to point me to an example or to a few tips about how to do it?

Thanks in advance.

[539 byte] By [jsl] at [2007-12-16]