Duplicate requests in SAP BC

Hi All,
I got an error in SAP BC. I am pasting the error log here…
IDoc was succesfully sent from SAP (Status:03). But I could not find them in SAP BC Transaction Logs. Can somebody please explain what is this error. Thanks.
Regards,
Phani Akella.

2007-06-19 15:55:42 GMT+00:00 [B2BCORE.0063.9116] [TxMgr] Duplicate request
at com.wm.app.b2b.server.TXJobMgr.executeJob(TXJobMgr.java:417)
at wm.server.tx.execute(tx.java:139)
at sun.reflect.GeneratedMethodAccessor12.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java(Compiled Code))
at java.lang.reflect.Method.invoke(Method.java(Compiled Code))
at com.wm.app.b2b.server.JavaService.baseInvoke(JavaService.java(Compiled Code))
at com.wm.app.b2b.server.ServiceManager.invoke(ServiceManager.java:709)
at com.wm.app.b2b.server.ServiceManager.invoke(ServiceManager.java:496)
at com.wm.app.b2b.server.HTTPInvokeHandler.process(HTTPInvokeHandler.java:207)
at com.wm.app.b2b.server.HTTPDispatch.run(HTTPDispatch.java:446)
at com.wm.util.pool.PooledThread.run(PooledThread.java:109)
at java.lang.Thread.run(Thread.java:566)