[Development] alpha build error Windows Seven

[qtnext]

Hi,

I am trying to build QT5 alpha using configure then perl build... It 
start fine (build a lot of dll), but failed when building qtxmlpatterns :

build qtxmlpatterns...
+ cd qtxmlpatterns && qmake -r
Could not find mkspecs for your QMAKESPEC(default) after trying:
         C:/dev/x32/qt5-a/qtxmlpatterns/mkspecs
         c:\dev\x32\qt5-a/mkspecs
cd qtxmlpatterns && qmake -r exited with status 768 at build line 64
         Qt::Build::exe('Qt::Build=HASH(0x35b320)', 'cd qtxmlpatterns && 
qmake -r
') called at build line 105
         Qt::Build::exeLowPriv('Qt::Build=HASH(0x35b320)', 'cd 
qtxmlpatterns && q
make -r') called at build line 373
         Qt::Build::build_project('Qt::Build=HASH(0x35b320)', 
'qtxmlpatterns') ca
lled at build line 408
         Qt::Build::build_qt('Qt::Build=HASH(0x35b320)') called at build 
line 437

         Qt::Build::run('Qt::Build=HASH(0x35b320)') called at build line 446