I have tried to change a lot of variables but I cannot find the right one:

Can anyone find it? Here is the debugging session:

C:\temp\victor\qtforusb\examples\chap03\spreadshee t>qmake spreadsheet.pro -d
DEBUG 1: Resetting dir to: C:/temp/victor/qtforusb/examples/chap03/spreadsheet\
DEBUG 1: Project Parser: c:\temp\victor\qtforusb\.qmake.cache:1 :QMAKE_QT_VERSION_OVERRIDE: :=: (4)
DEBUG 1: Project Parser: c:\temp\victor\qtforusb\.qmake.cache:2 :OBJECTS_DIR: :=: (tmp\obj\release_shared)
DEBUG 1: Project Parser: c:\temp\victor\qtforusb\.qmake.cache:3 :MOC_DIR: :=: (tmp\moc\release_shared)
DEBUG 1: Project Parser: c:\temp\victor\qtforusb\.qmake.cache:4 :RCC_DIR: :=: (tmp\rcc\release_shared)
DEBUG 1: Project Parser: c:\temp\victor\qtforusb\.qmake.cache:5 :sql-plugins: :+=: (odbc sqlite)
DEBUG 1: Project Parser: c:\temp\victor\qtforusb\.qmake.cache:6 :styles: :+=: (windows plastique cleanlooks windowsxp motif c
de)
DEBUG 1: Project Parser: c:\temp\victor\qtforusb\.qmake.cache:7 :imageformat-plugins: :+=: (jpeg)
DEBUG 1: Project Parser: c:\temp\victor\qtforusb\.qmake.cache:8 :CONFIG: :+=: (minimal-config small-config medium-config larg
e-config full-config release incremental create_prl link_prl depend_includepath)
DEBUG 1: Project Parser: c:\temp\victor\qtforusb\.qmake.cache:9 :QMAKESPEC: :=: (C:\temp\victor\qtforusb\mkspecs\win32-g++)
DEBUG 1: Project Parser: c:\temp\victor\qtforusb\.qmake.cache:10 :ARCH: :=: (windows)
DEBUG 1: Project Parser: c:\temp\victor\qtforusb\.qmake.cache:11 :QT_BUILD_TREE: :=: (C:\temp\victor\qtforusb)
DEBUG 1: Project Parser: c:\temp\victor\qtforusb\.qmake.cache:12 :QT_SOURCE_TREE: :=: (C:\temp\victor\qtforusb)
DEBUG 1: Project Parser: c:\temp\victor\qtforusb\.qmake.cache:13 :QMAKE_MOC: :=: (C:\temp\victor\qtforusb\bin\moc.exe)
DEBUG 1: Project Parser: c:\temp\victor\qtforusb\.qmake.cache:14 :QMAKE_UIC: :=: (C:\temp\victor\qtforusb\bin\uic.exe)
DEBUG 1: Project Parser: c:\temp\victor\qtforusb\.qmake.cache:15 :QMAKE_UIC3: :=: (C:\temp\victor\qtforusb\bin\uic3.exe)
DEBUG 1: Project Parser: c:\temp\victor\qtforusb\.qmake.cache:16 :QMAKE_RCC: :=: (C:\temp\victor\qtforusb\bin\rcc.exe)
DEBUG 1: Project Parser: c:\temp\victor\qtforusb\.qmake.cache:17 :QMAKE_DUMPCPP: :=: (C:\temp\victor\qtforusb\bin\dumpcpp.exe
)
DEBUG 1: Project Parser: c:\temp\victor\qtforusb\.qmake.cache:18 :QMAKE_INCDIR_QT: :=: (C:\temp\victor\qtforusb/include)
DEBUG 1: Project Parser: c:\temp\victor\qtforusb\.qmake.cache:19 :QMAKE_LIBDIR_QT: :=: (C:\temp\victor\qtforusb/lib)
Could not find mkspecs for your QMAKESPEC after trying:
C:\qtforusb\mkspecs
Error processing project file: spreadsheet.pro

C:\temp\victor\qtforusb\examples\chap03\spreadshee t>