[xml] libxml2mod.so: Symbol not found: _xmlTextReaderByteConsumed

[Marc Petitmermet <petitmermet mat ethz ch>]

dear list members

i'm trying to compile libxml2-2.6.19 on macosx 10.4 (tiger) for  
python-2.3.5 (i need this version because of zope). compilation  
itself is no problem but when making the tests, there is the  
following error for Relax-NG Python based test suite 1 and 2:

Traceback (most recent call last):
  File "./check-relaxng-test-suite.py", line 8, in ?
    import libxml2
  File "python/libxml2.py", line 1, in ?
    import libxml2mod
ImportError: dlopen(/Sources/libxml2-2.6.19/python/.libs/ 
libxml2mod.so, 2): Symbol not found: _xmlTextReaderByteConsumed
  Referenced from: /Sources/libxml2-2.6.19/python/.libs/libxml2mod.so
  Expected in: flat namespace

the same error occurs regardless of the python version used, i.e.  
self-compiled python-2.3.5 or system built-in python-2.3.5, and  
regardless of gcc version, i.e. 4.0 or 3.3.

does anybody know how this problem can be fixed? thanks in advance  
for any tips.

regards,
marc