jBOSS异常信息，请大家帮忙！

[ServiceController] Problem starting service com.jetstep.adaptoflow.engine:mbean=DService
java.lang.NoClassDefFoundError: java/net/URLDecoder
at org.springframework.beans.factory.xml.ResourceEntityResolver.resolveEntity(ResourceEntityResolver.java:70)
at org.apache.xerces.util.EntityResolverWrapper.resolveEntity(Unknown Source)
at org.apache.xerces.impl.XMLEntityManager.resolveEntity(Unknown Source)
at org.apache.xerces.impl.XMLDocumentScannerImpl$DTDDispatcher.dispatch(Unknown Source)
at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)
at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source)
at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source)
at org.apache.xerces.parsers.XMLParser.parse(Unknown Source)
at org.apache.xerces.parsers.DOMParser.parse(Unknown Source)
at org.apache.xerces.jaxp.DocumentBuilderImpl.parse(Unknown Source)请指出问题处在哪里?谢谢！