The old didn't have the path in Path and Libpath but had it listed in qtsys.conf in MPTN\etc.
%ETC%/qtsys.conf is no longer used. It was an OS/2 specific invention that - AFAIK - is valid only in 4.6.x version. Here is, how it works now:
The file qt.conf is searched in the specified order in following locations:
1.) in the (Qt-) resource data of the executable
2.) in the current directory
3.) in the directory where QtCore4.dll was loaded from
Then the "prefix" value from qt.conf is appended to the directory where qt.conf was found. This becomes the base directory for all the other stuff like "plugins", "translations", "imports", etc. Note that the names for these subdirs can be overridden - even with absolute paths - in qt.conf as well.
In case no qt.conf could be found, the directory where QtCore4.dll was loaded from will become the base and the subdirs will be assumed to use their default names.
The standard setup uses a directory structure like this:
%QTDIR%/bin
%QTDIR%/plugins
%QTDIR%/plugins/imageformats
...
%QTDIR%/translations
The Qt DLLs reside in %QTDIR%/bin. Thus qt.conf located in the same directory and found by rule 3.) must contain ".." as prefix value.
As I said rudi it was an extra dot in the path statement in the conf file for the new Qt4 version, a conf file I took as being correct but it wasn't for our situation.
So I assume you have changed the directory structure without knowing the implications. This is exactly the type of problems that this new RPM/YUM/FHS stuff is supposed to avoid. Not sure if it does...