this is my PATH and the migw\bin is fixed:

PATH=C:\apps\Tcl\bin;C:\apps\sniff\bin;C:\apps\sni ff\mks\mks-6.1\mksnt;C:\WINDOW
S\system32;C:\WINDOWS;C:\WINDOWS\SYSTEM32\Wbem;C:\ Archivos de programa\IVI\bin;C:\WINDOWS\system32\nls;C:\WINDOW S\system32\nls\ESPANOL; c:\MinGW\Bin;C:\WINDOWS\system32\nls;C:\WINDOWS\sy stem32\nls\ESPANOL;c:\qt\4.4.4\bin
;Z:.;

Maybe the problem could be that i dont have administration permission, although I didnt have any problem instaling qt-4.4.3 with the executable file.