Exception after upgrading to 0.85

I get the following exception after upgrading from 0.84 to 0.85. My server is running on ubuntu with python 2.4:

setp(axMiddle.get_xticklabels(), rotation=45, horizontalalignment='right', fontsize=7)
  File "/usr/lib/python2.4/site-packages/matplotlib/pylab.py", line 1551, in setp
    ret = _setp(*args, **kwargs)
  File "/usr/lib/python2.4/site-packages/matplotlib/artist.py", line 468, in setp
    insp = ArtistInspector(h)
  File "/usr/lib/python2.4/site-packages/matplotlib/artist.py", line 260, in __init__
    if iterable(o): o = o[0]
IndexError: list index out of range

any help would be appreciated.