Red Hat Enterprise Linux 6.3 registration is failing with "ImportError: /usr/lib64/python2.6/site-packages/_xmlplus/parsers/pyexpat.so: symbol XML_SetHashSalt, version EXPAT_2_0_1_RH not defined in file libexpat.so.1 with link time reference"

Issue

• Unable to register system when trying to execute rhn_register
• System registration to satellite via bootstrap script fails with below mentioned traceback:

Traceback (most recent call last):
  File "/usr/sbin/rhn_register", line 26, in <module>
    from up2date_client import tui
  File "/usr/share/rhn/up2date_client/tui.py", line 29, in <module>
    import rhnreg, hardware
  File "/usr/share/rhn/up2date_client/rhnreg.py", line 14, in <module>
    import dbus
  File "/usr/lib/python2.6/site-packages/dbus/__init__.py", line 100, in <module>
    from dbus._dbus import Bus, SystemBus, SessionBus, StarterBus
  File "/usr/lib/python2.6/site-packages/dbus/_dbus.py", line 46, in <module>
    from dbus.bus import BusConnection
  File "/usr/lib/python2.6/site-packages/dbus/bus.py", line 46, in <module>
    from dbus.connection import Connection
  File "/usr/lib/python2.6/site-packages/dbus/connection.py", line 42, in <module>
    from dbus.proxies import ProxyObject
  File "/usr/lib/python2.6/site-packages/dbus/proxies.py", line 35, in <module>
    from dbus._expat_introspect_parser import process_introspection_data
  File "/usr/lib/python2.6/site-packages/dbus/_expat_introspect_parser.py", line 26, in <module>
    from xml.parsers.expat import ExpatError, ParserCreate
  File "/usr/lib64/python2.6/site-packages/_xmlplus/parsers/expat.py", line 4, in <module>
    from pyexpat import *
ImportError: /usr/lib64/python2.6/site-packages/_xmlplus/parsers/pyexpat.so: symbol XML_SetHashSalt, version EXPAT_2_0_1_RH not defined in file libexpat.so.1 with link time reference