Warning when parsing some PPT

2013-07-03 11:52:45,332 [XWiki Solr index thread] WARN  a.t.p.m.AbstractPOIFSExtractor - Ignoring unexpected exception while parsing summary entry DocumentSummaryInformation 
java.lang.ClassCastException: [B cannot be cast to java.lang.String
	at org.apache.poi.hpsf.DocumentSummaryInformation.getCategory(DocumentSummaryInformation.java:78) ~[poi-3.9.jar:3.9]
	at org.apache.tika.parser.microsoft.SummaryExtractor.parse(SummaryExtractor.java:143) [tika-parsers-1.4.jar:na]
	at org.apache.tika.parser.microsoft.SummaryExtractor.parseSummaryEntryIfExists(SummaryExtractor.java:88) [tika-parsers-1.4.jar:na]
	at org.apache.tika.parser.microsoft.SummaryExtractor.parseSummaries(SummaryExtractor.java:73) [tika-parsers-1.4.jar:na]
	at org.apache.tika.parser.microsoft.OfficeParser.parse(OfficeParser.java:170) [tika-parsers-1.4.jar:na]
	at org.apache.tika.parser.microsoft.OfficeParser.parse(OfficeParser.java:161) [tika-parsers-1.4.jar:na]
	at org.apache.tika.parser.CompositeParser.parse(CompositeParser.java:242) [tika-core-1.4.jar:na]
	at org.apache.tika.parser.CompositeParser.parse(CompositeParser.java:242) [tika-core-1.4.jar:na]
	at org.apache.tika.parser.AutoDetectParser.parse(AutoDetectParser.java:120) [tika-core-1.4.jar:na]
	at org.apache.tika.Tika.parseToString(Tika.java:380) [tika-core-1.4.jar:na]
	at org.xwiki.search.solr.internal.metadata.AttachmentSolrMetadataExtractor.getContentAsText(AttachmentSolrMetadataExtractor.java:130) [xwiki-platform-search-solr-api-5.2-20130702.194010-10.jar:na]
	at org.xwiki.search.solr.internal.metadata.AttachmentSolrMetadataExtractor.setLocaleAndContentFields(AttachmentSolrMetadataExtractor.java:97) [xwiki-platform-search-solr-api-5.2-20130702.194010-10.jar:na]
	at org.xwiki.search.solr.internal.metadata.AttachmentSolrMetadataExtractor.setFieldsInternal(AttachmentSolrMetadataExtractor.java:79) [xwiki-platform-search-solr-api-5.2-20130702.194010-10.jar:na]
	at org.xwiki.search.solr.internal.metadata.AbstractSolrMetadataExtractor.getSolrDocument(AbstractSolrMetadataExtractor.java:114) [xwiki-platform-search-solr-api-5.2-20130702.194010-10.jar:na]
	at org.xwiki.search.solr.internal.DefaultSolrIndexer.getSolrDocument(DefaultSolrIndexer.java:465) [xwiki-platform-search-solr-api-5.2-20130702.194010-10.jar:na]
	at org.xwiki.search.solr.internal.DefaultSolrIndexer.processBatch(DefaultSolrIndexer.java:378) [xwiki-platform-search-solr-api-5.2-20130702.194010-10.jar:na]
	at org.xwiki.search.solr.internal.DefaultSolrIndexer.runInternal(DefaultSolrIndexer.java:353) [xwiki-platform-search-solr-api-5.2-20130702.194010-10.jar:na]
	at com.xpn.xwiki.util.AbstractXWikiRunnable.run(AbstractXWikiRunnable.java:121) [xwiki-platform-oldcore-5.2-20130702.190754-22.jar:na]
	at java.lang.Thread.run(Thread.java:680) [na:1.6.0_51]
2013-07-03 11:52:49,985 [Lucene Index Updater] WARN  a.t.p.m.AbstractPOIFSExtractor - Ignoring unexpected exception while parsing summary entry DocumentSummaryInformation 
java.lang.ClassCastException: [B cannot be cast to java.lang.String
	at org.apache.poi.hpsf.DocumentSummaryInformation.getCategory(DocumentSummaryInformation.java:78) ~[poi-3.9.jar:3.9]
	at org.apache.tika.parser.microsoft.SummaryExtractor.parse(SummaryExtractor.java:143) [tika-parsers-1.4.jar:na]
	at org.apache.tika.parser.microsoft.SummaryExtractor.parseSummaryEntryIfExists(SummaryExtractor.java:88) [tika-parsers-1.4.jar:na]
	at org.apache.tika.parser.microsoft.SummaryExtractor.parseSummaries(SummaryExtractor.java:73) [tika-parsers-1.4.jar:na]
	at org.apache.tika.parser.microsoft.OfficeParser.parse(OfficeParser.java:170) [tika-parsers-1.4.jar:na]
	at org.apache.tika.parser.microsoft.OfficeParser.parse(OfficeParser.java:161) [tika-parsers-1.4.jar:na]
	at org.apache.tika.parser.CompositeParser.parse(CompositeParser.java:242) [tika-core-1.4.jar:na]
	at org.apache.tika.parser.CompositeParser.parse(CompositeParser.java:242) [tika-core-1.4.jar:na]
	at org.apache.tika.parser.AutoDetectParser.parse(AutoDetectParser.java:120) [tika-core-1.4.jar:na]
	at org.apache.tika.Tika.parseToString(Tika.java:380) [tika-core-1.4.jar:na]
	at com.xpn.xwiki.plugin.lucene.internal.AttachmentData.getContentAsText(AttachmentData.java:221) [xwiki-platform-search-lucene-api-5.2-20130702.191134-22.jar:na]
	at com.xpn.xwiki.plugin.lucene.internal.AttachmentData.getFullText(AttachmentData.java:197) [xwiki-platform-search-lucene-api-5.2-20130702.191134-22.jar:na]
	at com.xpn.xwiki.plugin.lucene.internal.AbstractDocumentData.getFullText(AbstractDocumentData.java:251) [xwiki-platform-search-lucene-api-5.2-20130702.191134-22.jar:na]
	at com.xpn.xwiki.plugin.lucene.internal.AbstractDocumentData.addDocumentDataToLuceneDocument(AbstractDocumentData.java:212) [xwiki-platform-search-lucene-api-5.2-20130702.191134-22.jar:na]
	at com.xpn.xwiki.plugin.lucene.internal.AbstractDocumentData.addDataToLuceneDocument(AbstractDocumentData.java:147) [xwiki-platform-search-lucene-api-5.2-20130702.191134-22.jar:na]
	at com.xpn.xwiki.plugin.lucene.internal.AttachmentData.addDataToLuceneDocument(AttachmentData.java:99) [xwiki-platform-search-lucene-api-5.2-20130702.191134-22.jar:na]
	at com.xpn.xwiki.plugin.lucene.internal.IndexUpdater.addToIndex(IndexUpdater.java:296) [xwiki-platform-search-lucene-api-5.2-20130702.191134-22.jar:na]
	at com.xpn.xwiki.plugin.lucene.internal.IndexUpdater.updateIndex(IndexUpdater.java:237) [xwiki-platform-search-lucene-api-5.2-20130702.191134-22.jar:na]
	at com.xpn.xwiki.plugin.lucene.internal.IndexUpdater.runMainLoop(IndexUpdater.java:183) [xwiki-platform-search-lucene-api-5.2-20130702.191134-22.jar:na]
	at com.xpn.xwiki.plugin.lucene.internal.IndexUpdater.runInternal(IndexUpdater.java:168) [xwiki-platform-search-lucene-api-5.2-20130702.191134-22.jar:na]
	at com.xpn.xwiki.util.AbstractXWikiRunnable.run(AbstractXWikiRunnable.java:121) [xwiki-platform-oldcore-5.2-20130702.190754-22.jar:na]
	at java.lang.Thread.run(Thread.java:680) [na:1.6.0_51]