Parsing date throws exception

Progress
Starting job of type [wikistream.converter] with identifier [wikistream/converter/confluence+xml/xwiki+xar/1.1]
Unparseable date: "2012-08-31 17:23:31.477"
class java.text.ParseException: Unparseable date: "2012-08-31 17:23:31.477"
    at java.text.DateFormat.parse(DateFormat.java:357)
    at org.xwiki.wikistream.confluence.xml.internal.ConfluenceXMLPackage.getDate(ConfluenceXMLPackage.java:224)
    at org.xwiki.wikistream.confluence.xml.internal.input.ConfluenceInputWikiStream.readPage(ConfluenceInputWikiStream.java:292)
    at org.xwiki.wikistream.confluence.xml.internal.input.ConfluenceInputWikiStream.read(ConfluenceInputWikiStream.java:243)
    at org.xwiki.wikistream.confluence.xml.internal.input.ConfluenceInputWikiStream.read(ConfluenceInputWikiStream.java:56)
    at org.xwiki.wikistream.internal.input.AbstractBeanInputWikiStream.read(AbstractBeanInputWikiStream.java:78)
    at org.xwiki.wikistream.internal.job.WikiStreamConverterJob.runInternal(WikiStreamConverterJob.java:82)
    at org.xwiki.job.internal.AbstractJob.run(AbstractJob.java:154)
    at org.xwiki.wikistream.script.internal.ScriptWikiStreamConverterJob.run(ScriptWikiStreamConverterJob.java:75)
    at org.xwiki.job.internal.DefaultJobManager.runJob(DefaultJobManager.java:134)
    at org.xwiki.job.internal.DefaultJobManager.run(DefaultJobManager.java:113)
    at java.lang.Thread.run(Thread.java:744)