Error building qt windows 7: ld.exe: cannot find ljscore

[Ahas]

I'm trying to build QT on windows 7 width mingw width Webkit.

I'm getting the error ld.exe: cannot find -ljscore, and I can't find any solutions with Google.

I can't find a jscore.dll jscore.a jscore.lib or libjscore.dll or zomething similar on my system.

Does anyone know what went wrong?

Thanks

Edit: I just found libjscore.a somewhere in the qt sources and copied it to ming\lib.

I'm trying to compile right now, waiting to see if the problem is solved.

Edit 2:
dl.exe found libjscore.a but I got a lot of warnings: duplicate section ... for JSC::JSCell] has different size, and after those a lot of undefined references.
I think the libjscore.a I copied isn't the one I need.
I have no idea what to do now.