Export fails with Umlaut in image title

If you export a document with includes an image having a non ascii character (ä, ö, ü) the following exception is raised:

2013-08-22T10:52:40 ERROR Zope.SiteErrorLog 1377161560.140.715114162419 https://help.test.fhnw.ch/queries/test-umlaut-problem/@@asPDF
Traceback (innermost last):
  Module ZPublisher.Publish, line 60, in publish
  Module ZPublisher.mapply, line 77, in mapply
  Module ZPublisher.Publish, line 46, in call_object
  Module pp.client.plone.browser.pdf, line 207, in __call__
  Module pp.client.plone.browser.pdf, line 103, in __call__
  Module pp.client.plone.browser.pdf, line 169, in __call2__
  Module pp.client.plone.browser.pdf, line 98, in transformHtml
  Module pp.core.transformation, line 72, in __call__
  Module pp.client.plone.browser.transformations, line 100, in makeImagesLocal
  Module lxml.etree, line 2161, in lxml.etree._Attrib.__setitem__ (src/lxml/lxml.etree.c:48586)
  Module lxml.etree, line 563, in lxml.etree._setAttributeValue (src/lxml/lxml.etree.c:15481)
  Module lxml.etree, line 1369, in lxml.etree._utf8 (src/lxml/lxml.etree.c:22147)
ValueError: All strings must be XML compatible: Unicode or ASCII, no NULL bytes or control characters

Comments (2)