Qwt plugin on Qt Designer 4.7.3

[sonulohani]

edit "qtenv2.bat" instead. Paste the content like this---->
echo off
echo Setting up environment for Qt usage...
set QTDIR=C:\QtSDK\Desktop\Qt\4.7.4\mingw
set PATH=C:\QtSDK\mingw\bin;%PATH%
set PATH=%QTDIR%\bin;%PATH%
set PATH=%PATH%;C:\Qwt-6.0.1\lib
echo -- adding C:\Qwt-6.0.1\lib to PATH <-I