qmake's stdout/stderr output should not be split

Calling qmake on a SUBDIRS pro file which references a lot of projects gives the following warning for a customer:

For example:
[22] - WARNING: Failure to find: ..\..\common\source\PlatformIndependent\parserwrapper.h
To which of our 22 projects does this warning relate?

In order to investigate the problems, I can see no other solution but to open the projects one by one, which is painful given that we have 22 projects.

It would therefore be good if you could make it easier to associate the problems to the projects.