I have download the Qt binaries from QNX and installed it without getting any errors. I then installed Qt-creator from 
Ubuntu repository as well as the qnx-plugin. However, when I was setting up Qt development environment, like Qt version,
 I chose qt-qnx/Qt-5.3.1-x86/bin/qmake, it responded wtih qmake not executable. I tested it by running the qmake from 
command line, and it works.

I uninstalled it and reinstalled in different folder. Yet I got the same outcome- qmake not executable. However, 
Qtcreator does detect the other qmake in /usr/lib/x86_64-linux-gnu/qt5/bin.

1. Why the former qmake is detected as not executable?
2. Which qmake should I use? the from from Qnx or the one from Ubuntu?

Thank you