Hello,
Hello:
I faced the same problem while trying to use OpenCv library with Qt!
I am using:
1) OpenCv2.0
2) Qt Creator 2.01 Based on Qt 4.7.0 (32 bit)
3) Windows Xp

So I solved the problem by adding the following tags in the .pro file:

LIBS += -L C:\OpenCV2.0\bin -lcxcore200 -lcv200 -lcvaux200 -lhighgui200 -lml200 -lcxts200
INCLUDEPATH += C:/OpenCV2.0/include/opencv

Hope this will work