Memory leak in PyQt application

[Alexander Eisenhuth]

Hello alltogether,

My System:

Python 2.5.1
Boost.Python
Qt 4.2.2
SIP 4.6
PyQt 4.2
WinXp

I've a memory leak in a PyQt application and no idea how to find it. What 
happens in the application ?

 From QWindow a QDialog is called on a button "pressed()" signal, that 
instantiate a QThread and waits for it. If the thread has finished, the QDialog 
closes.

I've stipped down everything that nothing more happens (to me obviously). 
Boost.Python is used to wrap a C++ Lib (used in the thread). Every time memory 
usage increases for ~70 KB.

Sometimes the application crash on closing QWindow. (QtCore.dll)

- One thing I ask me is weather garbage collection is done in the PyQt main loop?

What hints do you have to find the leak?

Help is very very welcome

Regards
Alexander