I just want to report the same problem on linux(ubuntu), because on the windows works well. I have my applcation linked with latest version of GDAL, which don't have the same libpng version as Qt. My application project looks like:

QT -= core gui
GDALDIR = LIBS/GDAL/gdal-1.8
LIBS = -L$$GDALLIBDIR -lGDAL

When I try to open png file, libnpg say that it's linked with a newer version. Indeed when I debugged my application, it use the libpng open file function from Qt/3dparty/png instead of my GDAL. On windows platform works just fine.

Can someone explain how to solve this problem ?

Thanks