BTW, implementations for WCSToMBEx and MBToWCSEx can be found here: http://article.gmane.org/gmane.comp.emulators.wine.patches/5049/
I dont have a usable setup to turn them into proper patches but if anyone wants to use them for WINE, go ahead and grab them.
Not sure how usefull they would be but I suspect that they may bring WINE closer to the point where native WINIMM.DLL works.