All .7z files cause class not found exception in TikaExtractor

FATAL 2014-12-16 11:12:58,496 (Worker thread '47') - Error tossed: Could not initialize class org.apache.commons.compress.archivers.sevenz.Coders
java.lang.NoClassDefFoundError: Could not initialize class org.apache.commons.compress.archivers.sevenz.Coders
        at org.apache.commons.compress.archivers.sevenz.SevenZFile.readEncodedHeader(SevenZFile.java:279)
        at org.apache.commons.compress.archivers.sevenz.SevenZFile.readHeaders(SevenZFile.java:191)
        at org.apache.commons.compress.archivers.sevenz.SevenZFile.<init>(SevenZFile.java:95)
        at org.apache.commons.compress.archivers.sevenz.SevenZFile.<init>(SevenZFile.java:117)
        at org.apache.tika.parser.pkg.PackageParser.parse(PackageParser.java:130)
        at org.apache.tika.parser.CompositeParser.parse(CompositeParser.java:244)
        at org.apache.tika.parser.CompositeParser.parse(CompositeParser.java:244)
        at org.apache.tika.parser.AutoDetectParser.parse(AutoDetectParser.java:121)
        at org.apache.manifoldcf.agents.transformation.tika.TikaExtractor.addOrReplaceDocumentWithException(TikaExtractor.java:230)
        at org.apache.manifoldcf.agents.incrementalingest.IncrementalIngester$PipelineAddEntryPoint.addOrReplaceDocumentWithException(IncrementalIngester.java:3257)
        at org.apache.manifoldcf.agents.incrementalingest.IncrementalIngester$PipelineAddFanout.sendDocument(IncrementalIngester.java:3108)
        at org.apache.manifoldcf.agents.incrementalingest.IncrementalIngester$PipelineObjectWithVersions.addOrReplaceDocumentWithException(IncrementalIngester.java:2739)
        at org.apache.manifoldcf.agents.incrementalingest.IncrementalIngester.documentIngest(IncrementalIngester.java:792)
        at org.apache.manifoldcf.crawler.system.WorkerThread$ProcessActivity.ingestDocumentWithException(WorkerThread.java:1610)
        at org.apache.manifoldcf.crawler.system.WorkerThread$ProcessActivity.ingestDocumentWithException(WorkerThread.java:1558)
        at org.apache.manifoldcf.crawler.connectors.sharedrive.SharedDriveConnector.processDocuments(SharedDriveConnector.java:911)
        at org.apache.manifoldcf.crawler.system.WorkerThread.run(WorkerThread.java:383)