Hi,
I had no troubles installing Qt, Creator and Qwt on Rasbian Wheezy. The installed version was
Qt Creator 2.5.0
Based on Qt 4.8.1

Installation was done using:
sudo apt-get install qt4-dev-tools libqt4-dev qt4-qmake g++ make qtcreator
sudo apt-get install libqwt-dev libqwt-doc libqwt6
Uncheck "remote linux" and "Welcome" in QtCreator -> "Help" -> "About Plugins" ,
Adaption of toolchain in QtCreator

Everything works fine: compiling of Qt & Qwt programs without problems, Qwt Widgets in QtCreator are OK

BUT:
Using Jessie and installing Qt and QtCreator version is changed to:
Qt Creator 3.2.1
Based on Qt 5.3.2 (GCC 4.9.1)
I did not find a way to keep QtCreator 2.5 and Qt 4.8
This seems to be incompatible with Qwt when installing as above: there are no widgets of Qwt in QtCreator any longer!
Existing Qwt-programs can be compiled but working without widgets in QtCreator is annoying.
I also tried to compile Qwt manually and copying *.so-files to the plugin directory, but I was not sucessful.

So my question:
Does anybody know how to keep QtCreator 2.5 and Qt 4.8 in Jessie,
or how is Qwt installed correctly in Qt 5.3 and QtCreator 3.2

Thank you
Hans
PS: I also put this problem into the forum of raspberrypi.org, but I did not get any answer.