Index: src/java/org/sakaiproject/roster/impl/SakaiProxyImpl.java
===================================================================
--- src/java/org/sakaiproject/roster/impl/SakaiProxyImpl.java	(revision 314607)
+++ src/java/org/sakaiproject/roster/impl/SakaiProxyImpl.java	(working copy)
@@ -289,12 +289,14 @@ public class SakaiProxyImpl implements SakaiProxy
 			return null;
 		}
 
+		Map<String, User> userMap = getUserMap(membership);
+		Collection<Group> groups = site.getGroups();
 		for (Member member : membership) {
 
 			try {
 
 				RosterMember rosterMember = 
-					getRosterMember(member, site, includeConnectionStatus, userId);
+					getRosterMember(userMap, groups, member, site, includeConnectionStatus, userId);
 
 				rosterMembers.add(rosterMember);
 
@@ -311,6 +313,27 @@ public class SakaiProxyImpl implements SakaiProxy
 
 	}
 		
+    private Map<String, User> getUserMap(Set<Member> members) {
+        Map<String, User> userMap = new HashMap<String, User>();
+        Set<String> userIds = new HashSet<String>();
+        // Build a map of userId to role
+        for(Iterator<Member> iter = members.iterator(); iter.hasNext();)
+        {
+            Member member = iter.next();
+            if (member.isActive()) {
+				userIds.add(member.getUserId());
+	        }
+        }
+        // Get the user objects
+        List<User> users = userDirectoryService.getUsers(userIds);
+        for (Iterator<User> iter = users.iterator(); iter.hasNext();)
+        {
+            User user = iter.next();
+            userMap.put(user.getId(), user);
+        }
+        return userMap;
+    }
+		
 	private Map<String, RosterMember> getMembershipMapped(String siteId,
 			String groupId, boolean filtered) {
 
@@ -341,11 +364,13 @@ public class SakaiProxyImpl implements SakaiProxy
 			return null;
 		}
 
+		Map<String, User> userMap = getUserMap(membership);
+		Collection<Group> groups = site.getGroups();
 		for (Member member : membership) {
 
 			try {
 
-				RosterMember rosterMember = getRosterMember(member, site, false, userId);
+				RosterMember rosterMember = getRosterMember(userMap, groups, member, site, false, userId);
 
 				rosterMembers.put(rosterMember.getEid(), rosterMember);
 
@@ -504,12 +529,15 @@ public class SakaiProxyImpl implements SakaiProxy
 		return membership;
 	}
 	
-	private RosterMember getRosterMember(Member member, Site site,
+	private RosterMember getRosterMember(Map<String, User> userMap, Collection<Group> groups, Member member, Site site,
 			boolean includeConnectionStatus, String currentUserId) throws UserNotDefinedException {
 
 		String userId = member.getUserId();
 
-		User user = userDirectoryService.getUser(userId);
+		User user = userMap.get(userId);
+		if (user==null) {
+			throw new UserNotDefinedException(userId);
+		}
 
 		RosterMember rosterMember = new RosterMember(userId);
 		rosterMember.setEid(user.getEid());
@@ -520,14 +548,13 @@ public class SakaiProxyImpl implements SakaiProxy
 		rosterMember.setDisplayName(user.getDisplayName());
 		rosterMember.setSortName(user.getSortName());
 
-		Collection<Group> groups = site.getGroupsWithMember(userId);
-		Iterator<Group> groupIterator = groups.iterator();
-
-		while (groupIterator.hasNext()) {
-
-			Group group = groupIterator.next();
+		for (Group group : groups)
+		{
+			if (group.getMember(userId)!=null)
+			{
 			rosterMember.addGroup(group.getId(), group.getTitle());
 		}
+		}
 
         if (true == includeConnectionStatus && connectionsLogic != null) {
             rosterMember.setConnectionStatus(connectionsLogic