add workaround some transformation bug

tabellio/icalimport/icalimport.py

@@ -88,6 +88,12 @@ class IcalImport(BrowserView):
                 description = vevent.x_alt_desc.value
             except:
                 pass
+            if description and type(description) is unicode:
+                # there's some bug in the transformation chain that will at
+                # the wrong time convert the &nbsp and turn it into an invalid
+                # utf-8 character, therefore we replace all of them right now,
+                # as it's safe to do.
+                description = description.replace(' ', u'\xa0')
             if description:
                 event.text = RichTextValue(raw=description,
                         mimeType='text/html', outputMimeType='text/x-html-safe')