com.bea.wli.sb.context.BindingLayerException: General runtime error: Unknown error while processing message for ProxyService

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Applies To:
OSB - version 11.1.1.7.0
WLS - 10.3.6
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Problem:
Client was reporting that he is getting com.bea.wli.sb.context.BindingLayerException: General runtime error: Unknown error while processing message for ProxyService intermittently from few managed servers in a clustered environment.

Errors in log,

Caused By: com.bea.wli.sb.management.BrokerManagementException: java.lang.RuntimeException: com.bea.wli.sb.management.BrokerManagementException: com.bea.wli.sb.stages.StageException: The configured XQuery resource cannot be found.
                at com.bea.wli.sb.pipeline.RouterManager.getRouterRuntime(RouterManager.java:646)
                at com.bea.wli.sb.pipeline.RouterContext.getInstance(RouterContext.java:180)
                at com.bea.wli.sb.pipeline.RouterManager.processMessage(RouterManager.java:583)   at com.bea.wli.sb.transports.TransportManagerImpl.receiveMessage(TransportManagerImpl.java:398) at com.bea.wli.sb.transports.local.LocalTransportProvider.sendMessageAsync(LocalTransportProvider.java:322)     at sun.reflect.GeneratedMethodAccessor476.invoke(Unknown Source)   at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
                at java.lang.reflect.Method.invoke(Method.java:597)
{{{{{{{{{{{{{{{ Truncating }}}}}}}}}}}}}}}}}}}}}}
at oracle.tip.adapter.fw.jca.messageinflow.MessageEndpointImpl.onMessage(MessageEndpointImpl.java:556)   at oracle.tip.adapter.aq.v2.database.AbstractDequeueAgent$AQDeliveryBean.sendInboundRecord(AbstractDequeueAgent.java:571)        at oracle.tip.adapter.aq.v2.database.AbstractDequeueAgent.__AW_run(AbstractDequeueAgent.java:123)
                at oracle.tip.adapter.aq.v2.database.AbstractDequeueAgent.run(AbstractDequeueAgent.java)
                at java.lang.Thread.run(Thread.java:662)
Caused By: weblogic.xml.query.exceptions.XQueryTypeException: line 15, column 10: {err}XP0004: Invalid static type: (anyAttribute|PI)
                at weblogic.xml.query.compiler.TypeMatchExpression.typeCheckNoCache(TypeMatchExpression.java:144)
                at weblogic.xml.query.compiler.Expression.typeCheck(Expression.java:330)
                at weblogic.xml.query.compiler.FirstOrderExpression.typeCheckNoCache(FirstOrderExpression.java:269)
                at weblogic.xml.query.compiler.Expression.typeCheck(Expression.java:330)
                at weblogic.xml.query.compiler.IfThenElseExpression.typeCheckNoCache(IfThenElseExpression.java:112)
                at weblogic.xml.query.compiler.Expression.typeCheck(Expression.java:330)
                at weblogic.xml.query.compiler.GeneralFLWGDORExpression.typeCheckNoCache(GeneralFLWGDORExpression.java:404)
                at weblogic.xml.query.compiler.Expression.typeCheck(Expression.java:330)
                at weblogic.xml.query.compiler.NodeConstructor.typeCheckNoCache(NodeConstructor.java:278)

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Cause:

On investigation found that the root cause for com.bea.wli.sb.context.BindingLayerException: General runtime error: Unknown error while processing message for ProxyService is the configured XQuery resource which wasn't found at the run time. This was strange behavior because this is one of the server in cluster and has same copy like other where it's working fine. If we restart MS, it will resolve the issue temporarily but again will show up during peak load.

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Resolution:

After some research found one oracle note Doc ID 1679044.1 which says it's a bug and there is patch 18427728 available to resolve the issue.

After applying patch, we haven't seen error anymore during run time.