诡异问题

莫名其妙出现了~~[2011-04-05 11:05:25 - condi] Dx 
UNEXPECTED TOP-LEVEL EXCEPTION:
java.lang.IllegalArgumentException: already added: Lcom/sun/mail/imap/DefaultFolder$1;
[2011-04-05 11:05:25 - condi] Dx  at com.android.dx.dex.file.ClassDefsSection.add(ClassDefsSection.java:123)
[2011-04-05 11:05:25 - condi] Dx  at com.android.dx.dex.file.DexFile.add(DexFile.java:143)
[2011-04-05 11:05:25 - condi] Dx  at com.android.dx.command.dexer.Main.processClass(Main.java:372)
[2011-04-05 11:05:25 - condi] Dx  at com.android.dx.command.dexer.Main.processFileBytes(Main.java:346)
[2011-04-05 11:05:25 - condi] Dx  at com.android.dx.command.dexer.Main.access$400(Main.java:59)
[2011-04-05 11:05:25 - condi] Dx  at com.android.dx.command.dexer.Main$1.processFileBytes(Main.java:294)
[2011-04-05 11:05:25 - condi] Dx  at com.android.dx.cf.direct.ClassPathOpener.processArchive(ClassPathOpener.java:244)
[2011-04-05 11:05:25 - condi] Dx  at com.android.dx.cf.direct.ClassPathOpener.processOne(ClassPathOpener.java:130)
[2011-04-05 11:05:25 - condi] Dx  at com.android.dx.cf.direct.ClassPathOpener.process(ClassPathOpener.java:108)
[2011-04-05 11:05:25 - condi] Dx  at com.android.dx.command.dexer.Main.processOne(Main.java:313)
[2011-04-05 11:05:25 - condi] Dx  at com.android.dx.command.dexer.Main.processAllFiles(Main.java:233)
[2011-04-05 11:05:25 - condi] Dx  at com.android.dx.command.dexer.Main.run(Main.java:185)
[2011-04-05 11:05:25 - condi] Dx  at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
[2011-04-05 11:05:25 - condi] Dx  at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
[2011-04-05 11:05:25 - condi] Dx  at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
[2011-04-05 11:05:25 - condi] Dx  at java.lang.reflect.Method.invoke(Unknown Source)
[2011-04-05 11:05:25 - condi] Dx  at com.android.ide.eclipse.adt.internal.build.DexWrapper.run(DexWrapper.java:179)
[2011-04-05 11:05:25 - condi] Dx  at com.android.ide.eclipse.adt.internal.build.BuildHelper.executeDx(BuildHelper.java:585)
[2011-04-05 11:05:25 - condi] Dx  at com.android.ide.eclipse.adt.internal.build.builders.PostCompilerBuilder.build(PostCompilerBuilder.java:490)
[2011-04-05 11:05:25 - condi] Dx  at org.eclipse.core.internal.events.BuildManager$2.run(BuildManager.java:629)
[2011-04-05 11:05:25 - condi] Dx  at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
[2011-04-05 11:05:25 - condi] Dx  at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:172)
[2011-04-05 11:05:25 - condi] Dx  at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:203)
[2011-04-05 11:05:25 - condi] Dx  at org.eclipse.core.internal.events.BuildManager$1.run(BuildManager.java:255)
[2011-04-05 11:05:25 - condi] Dx  at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
[2011-04-05 11:05:25 - condi] Dx  at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:258)
[2011-04-05 11:05:25 - condi] Dx  at org.eclipse.core.internal.events.BuildManager.basicBuildLoop(BuildManager.java:311)
[2011-04-05 11:05:25 - condi] Dx  at org.eclipse.core.internal.events.BuildManager.build(BuildManager.java:343)
[2011-04-05 11:05:25 - condi] Dx  at org.eclipse.core.internal.events.AutoBuildJob.doBuild(AutoBuildJob.java:144)
[2011-04-05 11:05:25 - condi] Dx  at org.eclipse.core.internal.events.AutoBuildJob.run(AutoBuildJob.java:242)
[2011-04-05 11:05:25 - condi] Dx  at org.eclipse.core.internal.jobs.Worker.run(Worker.java:54)
[2011-04-05 11:05:25 - condi] Dx 1 error; aborting
[2011-04-05 11:05:25 - condi] Conversion to Dalvik format failed with error 1这是什么问题……完全不懂……