Error-"QT version is not properly installed,please run make install" on Ubuntu 10.10

Hey:
I just compiled Qt4.7.1 on Ubuntu 10.10 and everything went well,but at last I realized that I made a little mistake when run the configure scripts,the prefix was set "/usr/local/lib" while I wanted it to be "/usr/local/lib/Qt/4.7.1", then I just moved them to the right directory which is "/usr/local/lib/Qt/4.7.1" after install.
When I used QtCreator and point the qmake to the amentioned directory,it says "QT version is not properly installed,please run make install" and when I try to run qmake in the terminal, the generated makefile still has the include directory /usr/local/lib/include, which is wrong.
I have no idea what to do,please help.

Start over and give configure the correct path name. Do a 'make distclean' first, or - better yet - delete the unpacked source directory and start over completely, as Qt's cleaning scripts often miss things.