It looks like there's a bug setting start/end dates that ends up failing if you don't have admin on the group. The problem seems to be that if the checkboxes on that page aren't checked, it will call revokePriv on all the privileges.

2014-05-20 11:04:53,154: [TP-Processor2] ERROR GrouperUiRestServlet.doGet(309) - - Problem calling reflection from URL: edu.internet2.middleware.grouper.grouperUi.serviceLogic.UiV2Membership.saveMembership

edu.internet2.middleware.grouper.exception.RevokePrivilegeException: null, group name: test:testGroup, subject: Subject id: 0220198, sourceId: jndiperson, privilege: admin,
Problem in HibernateSession: HibernateSession: isNew: false, isReadonly: false, grouperTransactionType: READ_WRITE_NEW,
Problem in HibernateSession: HibernateSession: isNew: true, isReadonly: false, grouperTransactionType: READ_WRITE_NEW,
Problem calling method saveMembership on edu.internet2.middleware.grouper.grouperUi.serviceLogic.UiV2Membership
at edu.internet2.middleware.grouper.Group$11.callback(Group.java:4551)
at edu.internet2.middleware.grouper.hibernate.HibernateSession.callbackHibernateSession(HibernateSession.java:571)
at edu.internet2.middleware.grouper.Group.revokePriv(Group.java:4514)
at edu.internet2.middleware.grouper.Group$2.callback(Group.java:1114)
at edu.internet2.middleware.grouper.internal.dao.hib3.Hib3TransactionDAO$1.callback(Hib3TransactionDAO.java:66)
at edu.internet2.middleware.grouper.hibernate.HibernateSession.callbackHibernateSession(HibernateSession.java:571)
at edu.internet2.middleware.grouper.internal.dao.hib3.Hib3TransactionDAO.transactionCallback(Hib3TransactionDAO.java:56)
at edu.internet2.middleware.grouper.hibernate.GrouperTransaction.callbackGrouperTransaction(GrouperTransaction.java:87)
at edu.internet2.middleware.grouper.Group.addMember(Group.java:1062)
at edu.internet2.middleware.grouper.grouperUi.serviceLogic.UiV2Membership.saveMembership(UiV2Membership.java:888)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at edu.internet2.middleware.grouper.util.GrouperUtil.invokeMethod(GrouperUtil.java:3950)
at edu.internet2.middleware.grouper.util.GrouperUtil.callMethod(GrouperUtil.java:3901)
at edu.internet2.middleware.grouper.j2ee.GrouperUiRestServlet.doGet(GrouperUiRestServlet.java:276)
at edu.internet2.middleware.grouper.j2ee.GrouperUiRestServlet.doPost(GrouperUiRestServlet.java:160)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.owasp.csrfguard.CsrfGuardFilter.doFilter(CsrfGuardFilter.java:88)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at edu.internet2.middleware.grouper.ui.GrouperUiFilter.doFilter(GrouperUiFilter.java:984)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:190)
at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:291)
at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:774)
at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:703)
at org.apache.jk.common.ChannelSocket$SocketConnection.runIt(ChannelSocket.java:896)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:690)
at java.lang.Thread.run(Thread.java:662)
Caused by: edu.internet2.middleware.grouper.exception.UnableToPerformException
at edu.internet2.middleware.grouper.privs.AccessWrapper.revokePrivilege(AccessWrapper.java:237)
at edu.internet2.middleware.grouper.privs.AccessResolverDecorator.revokePrivilege(AccessResolverDecorator.java:258)
at edu.internet2.middleware.grouper.privs.AccessResolverDecorator.revokePrivilege(AccessResolverDecorator.java:258)
at edu.internet2.middleware.grouper.privs.CachingAccessResolver.revokePrivilege(CachingAccessResolver.java:224)
at edu.internet2.middleware.grouper.privs.AccessResolverDecorator.revokePrivilege(AccessResolverDecorator.java:258)
at edu.internet2.middleware.grouper.privs.ValidatingAccessResolver.revokePrivilege(ValidatingAccessResolver.java:191)
at edu.internet2.middleware.grouper.Group$11.callback(Group.java:4528)
... 40 more
Caused by: edu.internet2.middleware.grouper.exception.InsufficientPrivilegeException
at edu.internet2.middleware.grouper.privs.GrouperNonDbAccessAdapter.revokePriv(GrouperNonDbAccessAdapter.java:522)
at edu.internet2.middleware.grouper.privs.AccessWrapper.revokePrivilege(AccessWrapper.java:234)
... 46 more