diff --git a/chrome/content/zotero/xpcom/connector/connector.js b/chrome/content/zotero/xpcom/connector/connector.js
index 7a98b2cd5..79af62367 100644
--- a/chrome/content/zotero/xpcom/connector/connector.js
+++ b/chrome/content/zotero/xpcom/connector/connector.js
@@ -25,7 +25,7 @@
 
 Zotero.Connector = new function() {
 	const CONNECTOR_URI = "http://127.0.0.1:23119/";
-	const CONNECTOR_SERVER_API_VERSION = 1;
+	const CONNECTOR_API_VERSION = 2;
 	
 	this.isOnline = null;
 	
@@ -69,8 +69,18 @@ Zotero.Connector = new function() {
 				}
 				
 				if(Zotero.Connector.EXCEPTION_CODES.indexOf(req.status) !== -1) {
-					Zotero.debug("Connector: Method "+method+" failed");
+					Zotero.debug("Connector: Method "+method+" failed with status "+req.status);
 					if(callback) callback(false, req.status);
+					
+					// Check for incompatible version
+					if(req.status === 404 || req.status === 412) {
+						if(Zotero.Connector_Browser && Zotero.Connector_Browser.onIncompatibleStandaloneVersion) {
+							var standaloneVersion = req.getResponseHeader("X-Zotero-Version");
+							Zotero.Connector_Browser.onIncompatibleStandaloneVersion(Zotero.version, standaloneVersion);
+							throw "Connector: Version mismatch: Connector version "+Zotero.version
+								+", Standalone version "+(standaloneVersion ? standaloneVersion : "<unknown>");
+						}
+					}
 				} else {
 					Zotero.debug("Connector: Method "+method+" succeeded");
 					var val = null;
@@ -91,6 +101,10 @@ Zotero.Connector = new function() {
 		var uri = CONNECTOR_URI+"connector/"+method;
 		
 		Zotero.HTTP.doPost(uri, JSON.stringify(data),
-			newCallback, {"Content-Type":"application/json"});
+			newCallback, {
+				"Content-Type":"application/json",
+				"X-Zotero-Version":Zotero.version,
+				"X-Zotero-Connector-API-Version":CONNECTOR_API_VERSION
+		});
 	}
 }
\ No newline at end of file
diff --git a/chrome/content/zotero/xpcom/server.js b/chrome/content/zotero/xpcom/server.js
index 2e7a14a4e..c6a4ffcc8 100755
--- a/chrome/content/zotero/xpcom/server.js
+++ b/chrome/content/zotero/xpcom/server.js
@@ -67,6 +67,10 @@ Zotero.Server = new function() {
 	 */
 	this.generateResponse = function (status, contentType, body) {
 		var response = "HTTP/1.0 "+status+" "+responseCodes[status]+"\r\n";
+		if(!Zotero.isServer) {
+			response += "X-Zotero-Version: "+Zotero.version+"\r\n";
+			response += "X-Zotero-Connector-API-Version: "+CONNECTOR_API_VERSION+"\r\n";
+		}
 		
 		if(body) {
 			if(contentType) {
diff --git a/chrome/content/zotero/xpcom/server_connector.js b/chrome/content/zotero/xpcom/server_connector.js
index fd90687c1..ddcc44629 100755
--- a/chrome/content/zotero/xpcom/server_connector.js
+++ b/chrome/content/zotero/xpcom/server_connector.js
@@ -1,7 +1,7 @@
 /*
     ***** BEGIN LICENSE BLOCK *****
     
-    Copyright © 2009 Center for History and New Media
+    Copyright © 2011 Center for History and New Media
                      George Mason University, Fairfax, Virginia, USA
                      http://zotero.org
     
@@ -22,8 +22,7 @@
     
     ***** END LICENSE BLOCK *****
 */
-
-const CONNECTOR_SERVER_API_VERSION = 2;
+const CONNECTOR_API_VERSION = 2;
 
 Zotero.Server.Connector = function() {};
 Zotero.Server.Connector._waitingForSelection = {};
@@ -406,4 +405,9 @@ Zotero.Server.Connector.Ping.prototype = {
 	"init":function(postData, sendResponseCallback) {
 		sendResponseCallback(200);
 	}
-}
\ No newline at end of file
+}
+
+
+// XXX For compatibility with older connectors; to be removed
+Zotero.Server.Endpoints["/translate/list"] = Zotero.Server.Connector.GetTranslators;
+Zotero.Server.Endpoints["/translate/save"] = Zotero.Server.Connector.SavePage;
\ No newline at end of file