See following bug report at Ubuntu https://bugs.launchpad.net/bugs/129389 There you find all info: Command line, stack trace, ...
The Ubuntu bug report has now a symbolic stack race added.
Now all we need is a test file.
The name of the file is known from the stack trace ( MPR_naive_2.eps ) but this file name is not known to any search engines. The author of the original bug report didn't post the file - even after he was asked to do so. There's nothing else I can do to reproduce the problem. The bug is closed as invalid.