hi andre,
i finally found the mistake, my preprocessor symbols where messed up. everything works not with only _DEBUG and WXUSINGDLL. i did not really understand preprocessor symbols before, so i just tried different things that i found on the internet without knowing what i was doing.
i also built wx from the standard wx_dll.dsw file, not the special one from wx291_msw_vc10.zip from one of my earlier posts. maybe that was also important.
about your last post, the preprocessor symbols in the wx build included DLL_EXPORTS, so everything was fine there. i just did not use the dll version of wx in my project.
thank you VERY much for taking the time to help me and being patient with my half-knowledge (is this a word in english, we use it in German).