I have a problem. It seems to be rather simple but I can not find how to solve it

I have my project being compiled under VS2003. I decided to try to compile it with VS2005. So I installed VS2005 and Qt libs for VS2005. And now when I'm trying to generate .vcproj files for VS2005 from my .pro files then I have the following message from qmake in console:

WARNING: Generator: MSVC.NET: Found more than one version of Visual Studio, but
none in your path! Fallback to lowest version (MSVC.NET 2005 (8.0), MSVC.NET 200
3 (7.1))

Does anybody know what is that and how to solve this? Thanks in advance