When I try to render any equation in Inkscape, I get the error message included below.

I went digging in the temporary files that Inkscape generates, and all the tex and ps files are there, and they have been created without a problme, but the svg file is nowhere to be found. To me that indicates that maybe the problem is the creation of the svg that fails for some reason. So I tried running the pstoedit command which is executed in eqtexsvg directly from the command line, and that works without a problem -- I get the svg, and it looks fine in Firefox (it is also included below). I tried editing eqtexsvg so that the full path to pstoedit was hardcoded, but that did not change the behaviour at all.

My conclusion (which may be incorrect) is that the version of pstoedit I have installed has problems with the libraries which are included in the OSX version of Inkscape I am using (0.46.3). I use MacPorts, and everything seems to be up to date. If anything, the error seems to indicate that my version is _too recent_ for the libraries included in Inkscape.

Has anyone encountered this problem and solved it? Is there are clear way to get around this problem? I'd really like to make Inkscape my tool for illustrating my research papers ...

pstoedit: version 3.45 / DLL interface 108 (build Aug 12 2008 - release build - g++ 4.0.1 (Apple Inc. build 5465)) : Copyright (C) 1993 - 2007 Wolfgang Glunz
Problem during opening /opt/local/lib/pstoedit/libp2edrvlplot.0.0.0.so:dlopen(/opt/local/lib/pstoedit/libp2edrvlplot.0.0.0.so, 1): Library not loaded: /opt/local/lib/libpng12.0.dylib
Referenced from: /opt/local/lib/pstoedit/libp2edrvlplot.0.0.0.so
Reason: Incompatible library version: libp2edrvlplot.0.0.0.so requires version 30.0.0 or later, but libpng12.0.dylib provides version 27.0.0
Problem during opening of pstoedit driver plugin: /opt/local/lib/pstoedit/libp2edrvlplot.0.0.0.so. This is no problem as long the driver in this library is not needed. Possibly you need to install further libraries and/or extend the LD_LIBRARY_PATH (*nix) or PATH (Windows) environment variables.
Problem during opening /opt/local/lib/pstoedit/libp2edrvlplot.0.so:dlopen(/opt/local/lib/pstoedit/libp2edrvlplot.0.so, 1): Library not loaded: /opt/local/lib/libpng12.0.dylib
Referenced from: /opt/local/lib/pstoedit/libp2edrvlplot.0.so
Reason: Incompatible library version: libp2edrvlplot.0.so requires version 30.0.0 or later, but libpng12.0.dylib provides version 27.0.0
Problem during opening of pstoedit driver plugin: /opt/local/lib/pstoedit/libp2edrvlplot.0.so. This is no problem as long the driver in this library is not needed. Possibly you need to install further libraries and/or extend the LD_LIBRARY_PATH (*nix) or PATH (Windows) environment variables.
Problem during opening /opt/local/lib/pstoedit/libp2edrvlplot.so:dlopen(/opt/local/lib/pstoedit/libp2edrvlplot.so, 1): Library not loaded: /opt/local/lib/libpng12.0.dylib
Referenced from: /opt/local/lib/pstoedit/libp2edrvlplot.so
Reason: Incompatible library version: libp2edrvlplot.so requires version 30.0.0 or later, but libpng12.0.dylib provides version 27.0.0
Problem during opening of pstoedit driver plugin: /opt/local/lib/pstoedit/libp2edrvlplot.so. This is no problem as long the driver in this library is not needed. Possibly you need to install further libraries and/or extend the LD_LIBRARY_PATH (*nix) or PATH (Windows) environment variables.
Traceback (most recent call last):
File "Contents/Resources/extensions/eqtexsvg.py", line 119, in <module>
e.affect()
File "/Applications/Inkscape.app/Contents/Resources/extensions/inkex.py", line 154, in affect
self.effect()
File "Contents/Resources/extensions/eqtexsvg.py", line 114, in effect
svg_open(self, svg_file)
File "Contents/Resources/extensions/eqtexsvg.py", line 67, in svg_open
doc = inkex.etree.parse(filename)
File "etree.pyx", line 2045, in etree.parse
File "parser.pxi", line 970, in etree._parseDocument
File "parser.pxi", line 974, in etree._parseDocumentFromURL
File "parser.pxi", line 891, in etree._parseDocFromFile
File "parser.pxi", line 582, in etree._BaseParser._parseDocFromFile
File "parser.pxi", line 656, in etree._handleParseResult
File "parser.pxi", line 622, in etree._raiseParseError
IOError: Error reading file '/var/folders/Xa/XaqHO9PeEC8K-Nrd0L9xWk+++TM/-Tmp-/inkscape-UJr2T5/eq.svg': failed to load external entity "/var/folders/Xa/XaqHO9PeEC8K-Nrd0L9xWk+++TM/-Tmp-/inkscape-UJr2T5/eq.svg"

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