Deleting the last member from a group using Remove selected members button creates a java excption

When a group has a single direct member, and that member is removed using the "Remove selected members" button on the Current Members page, the action page throws a java exception. The member can be deleted using the "Remove all members" button. Furthermore, the Remove selected members" button succeeds for any number of users < n. But if the number of users removed = n, the same null GroupNotFoundException results.

Unexpected error - edu.internet2.middleware.grouper.GroupNotFoundException:null
An error has occurred which prevented the page from displaying. If the problem persists please contact your system administrator with the details below:

edu.internet2.middleware.grouper.GroupNotFoundException at edu.internet2.middleware.grouper.internal.dao.hibernate.HibernateGroupDAO.findByUuid(HibernateGroupDAO.java:519) at edu.internet2.middleware.grouper.GroupFinder.findByUuid(GroupFinder.java:171) at edu.internet2.middleware.grouper.ui.actions.RemoveGroupMembersAction.grouperExecute(RemoveGroupMembersAction.java:158) at edu.internet2.middleware.grouper.ui.actions.GrouperCapableAction.execute(GrouperCapableAction.java:223) at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:421) at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:226) at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1164) at org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:415) at javax.servlet.http.HttpServlet.service(HttpServlet.java:710) at javax.servlet.http.HttpServlet.service(HttpServlet.java:803) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:269) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188) at edu.internet2.middleware.grouper.ui.LoginCheckFilter.doFilter(LoginCheckFilter.java:167) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:201) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:174) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:433) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:117) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:108) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:151) at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:200) at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:283) at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:773) at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:703) at org.apache.jk.common.ChannelSocket$SocketConnection.runIt(ChannelSocket.java:895) at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:685) at java.lang.Thread.run(Thread.java:595)