OSX 10.5.4, libpng12.0.dylib

After installing Panda3D 1.7, getting this error:

Traceback (most recent call last):
  File "robot.py", line 2, in <module>
    from pandac.PandaModules import *
  File "/Developer/Panda3D/lib/pandac/PandaModules.py", line 8, in <module>
    from libpandaModules import *
  File "/Developer/Panda3D/lib/pandac/libpandaModules.py", line 2, in <module>
    Dtool_PreloadDLL("libpanda")
  File "/Developer/Panda3D/lib/pandac/extension_native_helpers.py", line 79, in Dtool_PreloadDLL
    imp.load_dynamic(module, pathname)
ImportError: dlopen(/Developer/Panda3D/lib/libpanda.dylib, 2): Library not loaded: /usr/X11/lib/libpng12.0.dylib
  Referenced from: /Developer/Panda3D/lib/libpanda.dylib
  Reason: Incompatible library version: libpanda.dylib requires version 27.0.0 or later, but libpng12.0.dylib provides version 25.0.0

strange …

Hm… have you considered a software update?