Undefined function, even though imported

[Loopback]

Thanks for your answer!

Seems like supplying with the file location solved the problem, though I 
still wonder about one thing. The imported module is located in 
"c:/d/dmd2/import/win32/windef.d" and I have used this command line to 
the DMD compiler: -I"c:/d/dmd2/import/". Shouldn't the linker/compiler 
be able to solve this on its own then?