Using Designer 8.1/Teiid 8.3 and executing against the following:
http://gw.esworkplace.sap.com/sap/opu/sdata/iwcnt/contact/ContactCollection?sap-client=800&$format=xml&$filter=SearchTerm%20eq%20%27*%27

gives me the following NPE:

13:00:28,345 ERROR [org.teiid.PROCESSOR] (Worker0_QueryProcessorQueue25) YH9sbL1HZbxJ TEIID30019 Unexpected exception for request YH9sbL1HZbxJ.6: java.lang.NullPointerException
at org.teiid.translator.ws.BinaryWSProcedureExecution.getOutputParameterValues(BinaryWSProcedureExecution.java:178)
at org.teiid.dqp.internal.datamgr.ProcedureBatchHandler.getParameterRow(ProcedureBatchHandler.java:86) [teiid-engine-8.3.0.Final.jar:8.3.0.Final]
at org.teiid.dqp.internal.datamgr.ConnectorWorkItem.handleBatch(ConnectorWorkItem.java:356) [teiid-engine-8.3.0.Final.jar:8.3.0.Final]
at org.teiid.dqp.internal.datamgr.ConnectorWorkItem.more(ConnectorWorkItem.java:141) [teiid-engine-8.3.0.Final.jar:8.3.0.Final]
at org.teiid.dqp.internal.process.DataTierTupleSource.getResults(DataTierTupleSource.java:467) [teiid-engine-8.3.0.Final.jar:8.3.0.Final]
at org.teiid.dqp.internal.process.DataTierTupleSource$1.call(DataTierTupleSource.java:178) [teiid-engine-8.3.0.Final.jar:8.3.0.Final]
at org.teiid.dqp.internal.process.DataTierTupleSource$1.call(DataTierTupleSource.java:175) [teiid-engine-8.3.0.Final.jar:8.3.0.Final]
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303) [classes.jar:1.6.0_45]
at java.util.concurrent.FutureTask.run(FutureTask.java:138) [classes.jar:1.6.0_45]
at org.teiid.dqp.internal.process.DQPCore$FutureWork.run(DQPCore.java:120) [teiid-engine-8.3.0.Final.jar:8.3.0.Final]
at org.teiid.dqp.internal.process.DQPWorkContext.runInContext(DQPWorkContext.java:264) [teiid-engine-8.3.0.Final.jar:8.3.0.Final]
at org.teiid.dqp.internal.process.ThreadReuseExecutor$RunnableWrapper.run(ThreadReuseExecutor.java:123) [teiid-engine-8.3.0.Final.jar:8.3.0.Final]
at org.teiid.dqp.internal.process.ThreadReuseExecutor$3.run(ThreadReuseExecutor.java:298) [teiid-engine-8.3.0.Final.jar:8.3.0.Final]
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:895) [classes.jar:1.6.0_45]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:918) [classes.jar:1.6.0_45]
at java.lang.Thread.run(Thread.java:680) [classes.jar:1.6.0_45]