i found this solution:

http://www.dnncreative.com/Forum/tabid/88/aft/24514/%5BLink%5D "I figured it out. I was including the whole directory with the control in it into my child projects. Subsequently the .vb codebehinds, with their namespace declarations, were being compiled into the project module DLLs and never being referenced from the subcontrols own DLL. That's why it worked with one module on the system but not both of them. When I removed the .vb scripts (and the project reference back to the subcontrol project) from the main module projects, leaving just the ascx file, the ascx file had to get it's code from it's own precompiled DLL and all was right. Both controls could use the same precompiled DLL and just use the ascx and the DLL, not the vb source."

But now i can't see my labels. The resource file isn't picked up. Anybody an idea?