Linking error with MinGW gcc and Gecko SDK cygwin

Hello!
I'm currently writing an XPCOM C++ extension for Firefox . I am having
linking problems. I downloade the msvc and cygwin Gecko SDKs and I've
tried every technique under the sun to expose xpcom.dll to the mingw
g++ compiler & linker.

I've tried linking the dll and the *.lib files that come with the
gecko SDK to the mingw g++ world. No dice.

The best I can come up with is converting the dll and the lib files
into *.a achives and I keep having a linking problem to the effect of:

> 'undefined reference to nsMemory::Clone(void const*, unsigned int)'
> 'undefined reference to NS_NewGenericModule2(nsModuleInfo *, nsIModule **)'

I'm working with the latest MinGW and Windows XP

Thanks for listening!

Christopher Taylor