StdSchedulerFactory.getDefaultScheduler() 这个调度器启动报错，求解！急

import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;

import org.quartz.SchedulerException;


/**
 * 类说明：定时执行监听类
 * @author huqy
 */
public class InterfaceSchedulerListener implements ServletContextListener {

	public void contextInitialized(ServletContextEvent arg0) {
		try {
			InvSchedule invschedule = new InvSchedule();
			invschedule.loadScheduler();
			System.out.println("quartz定时器已启动======================================");
		} catch (SchedulerException e) {
			e.printStackTrace();
		}
	}
	
	public void contextDestroyed(ServletContextEvent arg0) {
		System.out.println("接口任务调度器已终止调度！");
	}

}

import org.quartz.CronTrigger;
import org.quartz.JobDetail;
import org.quartz.Scheduler;
import org.quartz.SchedulerException;
import org.quartz.impl.StdSchedulerFactory;

/**
 * @function 定时执行类
 * @author huqy
 *
 */
public class InvSchedule{

	public final static String JOB_GROUP_NAME = "INV_GROUP_JOB";
	public final static String TRIG_GROUP_NAME = "INV_GROUP_TRIG";

	public void loadScheduler() throws SchedulerException {
		Scheduler scheduler = null;
		try{
			scheduler = StdSchedulerFactory.getDefaultScheduler();//这里报错了  错误信息如下
			scheduler.start();
			//定时开关 ON==开   OFF==关 
			if(InvConfig.getInstance().getJobswitch("job.switch").equals("ON")){
				/**
				 * 用户机构 定时同步
				 */
				JobDetail jobDetail = new JobDetail("INTERFACE_SCHEDULE",JOB_GROUP_NAME,this.getClass().forName("com.nci.inv.webservice.InvUserAndOrgJob"));
				CronTrigger ct = new CronTrigger("INTERFACE_SCHEDULE1",TRIG_GROUP_NAME,InvConfig.getInstance().getTime("userandorg.time"));
				scheduler.scheduleJob(jobDetail, ct);
				
				}
		} catch (Exception e){
			System.out.println("启动-INTERFACE_SCHEDULE-计划任务失败！");
			e.printStackTrace();
		}

	}

}

接口任务调度器已终止调度！
2012-4-12 17:03:06 org.apache.catalina.core.StandardContext processTlds
严重: Error reading tld listeners java.lang.NullPointerException
java.lang.NullPointerException
at org.apache.log4j.spi.LocationInfo.<init>(LocationInfo.java:95)
at org.apache.log4j.spi.LoggingEvent.getLocationInformation(LoggingEvent.java:182)
at org.apache.log4j.helpers.PatternParser$LocationPatternConverter.convert(PatternParser.java:475)
at org.apache.log4j.helpers.PatternConverter.format(PatternConverter.java:56)
at org.apache.log4j.PatternLayout.format(PatternLayout.java:495)
at org.apache.log4j.WriterAppender.subAppend(WriterAppender.java:292)
at org.apache.log4j.DailyRollingFileAppender.subAppend(DailyRollingFileAppender.java:349)
at org.apache.log4j.WriterAppender.append(WriterAppender.java:150)
at org.apache.log4j.AppenderSkeleton.doAppend(AppenderSkeleton.java:221)
at org.apache.log4j.helpers.AppenderAttachableImpl.appendLoopOnAppenders(AppenderAttachableImpl.java:57)
at org.apache.log4j.Category.callAppenders(Category.java:187)
at org.apache.log4j.Category.forcedLog(Category.java:372)
at org.apache.log4j.Category.log(Category.java:864)
at org.apache.commons.logging.impl.Log4JLogger.debug(Log4JLogger.java:110)
at org.apache.catalina.startup.TldConfig.tldScanResourcePaths(TldConfig.java:575)
at org.apache.catalina.startup.TldConfig.execute(TldConfig.java:282)
at org.apache.catalina.core.StandardContext.processTlds(StandardContext.java:4307)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4144)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:760)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:740)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:544)
at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:927)
at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:890)
at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:492)
at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1150)
at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:311)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:120)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1022)
at org.apache.catalina.core.StandardHost.start(StandardHost.java:736)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1014)
at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443)
at org.apache.catalina.core.StandardService.start(StandardService.java:448)
at org.apache.catalina.core.StandardServer.start(StandardServer.java:700)
at org.apache.catalina.startup.Catalina.start(Catalina.java:552)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:295)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:433)