type error complaint

A problem I don't understand with matplotlib. This used to work, until I
upgraded. Now running

dev-lang/python-2.4.3-r4
dev-python/numpy-1.0
dev-python/matplotlib-0.87.7
sci-libs/scipy-0.5.1-r1

on a Gentoo Linux system :

2.6.16-gentoo-r3
AMD Athlon 64 X2 3800+

$ ~/lib/python/weatherlib_alpha.py
/usr/lib/python2.4/site-packages/wx-2.6-gtk2-ansi/wx/_core.py:13155: UserWarning: wxPython/wxWidgets release number mismatch
  warnings.warn("wxPython/wxWidgets release number mismatch")
/usr/lib/python2.4/calendar.py:105: DeprecationWarning: integer argument expected, got float
  return datetime.date(year, month, day).weekday()
/usr/lib/python2.4/site-packages/dateutil/relativedelta.py:271: DeprecationWarning: integer argument expected, got float
  ret = (other.replace(**repl)
Traceback (most recent call last):
  File "/home/ajackson/lib/python/weatherlib_alpha.py", line 228, in ?
    WD = wpanel(WD_defs)
  File "/home/ajackson/lib/python/weatherlib_alpha.py", line 138, in __init__
    self.Cax_c = figtext(0.84, .1, 'OOO')
  File "/usr/lib/python2.4/site-packages/matplotlib/pylab.py", line 776, in figtext
    draw_if_interactive()
  File "/usr/lib/python2.4/site-packages/matplotlib/backends/backend_wx.py", line 1172, in draw_if_interactive
    figManager.canvas.draw()
  File "/usr/lib/python2.4/site-packages/matplotlib/backends/backend_wxagg.py", line 61, in draw
    FigureCanvasAgg.draw(self)
  File "/usr/lib/python2.4/site-packages/matplotlib/backends/backend_agg.py", line 392, in draw
    self.figure.draw(renderer)
  File "/usr/lib/python2.4/site-packages/matplotlib/figure.py", line 544, in draw
    for a in self.axes: a.draw(renderer)
  File "/usr/lib/python2.4/site-packages/matplotlib/axes.py", line 1063, in draw
    a.draw(renderer)
  File "/usr/lib/python2.4/site-packages/matplotlib/axis.py", line 559, in draw
    tick.set_label1(label)
  File "/usr/lib/python2.4/site-packages/matplotlib/axis.py", line 188, in set_label1
    self.label1.set_text(s)
  File "/usr/lib/python2.4/site-packages/matplotlib/text.py", line 671, in set_text
    raise TypeError("This doesn't look like a string: '%s'"%s)
TypeError: This doesn't look like a string: '0.0'

···

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Alan K. Jackson | To see a World in a Grain of Sand |
alan@...895... | And a Heaven in a Wild Flower, |
www.ajackson.org | Hold Infinity in the palm of your hand |
Houston, Texas | And Eternity in an hour. - Blake |

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