Error WX_Agg backend with0.91.1 on OS X 10.5 Leopard

Installed MatPlotLib 0.91.1 on OS X 10.5 Leopard (intel)

When saving plot files to formats .png or .svg I get the following error.

Matplotlib backend_wx_error cannot return std::string from Unicode object

This errors occurs with both wxpython 2.8.30 and 2.8.7.1

.ps .eps and .pdf works fine. Anyone seen this error?

I tried to install 0.91.2 but it failed (see other post)

My Configuration:
http://www.python.org/ftp/python/2.5.2/python-2.5.2-macosx.dmg
http://www.pythonmac.org/packages/py25-fat/dmg/matplotlib-0.91.1-py2.5-macosx10.4-2007-12-04.dmg
http://www.pythonmac.org/packages/py25-fat/dmg/numpy-1.0.4-py2.5-macosx10.4-2007-11-07.dmg
http://www.pythonmac.org/packages/py25-fat/dmg/wxPython2.8-osx-unicode-2.8.3.0-universal10.4-py2.5.dmg

or
http://downloads.sourceforge.net/wxpython/wxPython2.8-osx-unicode-2.8.7.1-universal-py2.5.dmg

ยทยทยท

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