diff --git a/server/go/camlistored/camlistored.go b/server/go/camlistored/camlistored.go
index b6f83cb8e..fe6ac8e92 100644
--- a/server/go/camlistored/camlistored.go
+++ b/server/go/camlistored/camlistored.go
@@ -279,6 +279,8 @@ func configFileMain() {
 			installHandler(createRootHandler)
 		case handlerType == "ui":
 			installHandler(createUIHandler)
+		case handlerType == "jsonsign":
+			installHandler(createJSONSignHandler)
 		default:
 			// Assume a storage interface
 			pstorage, err := blobserver.CreateStorage(handlerType, jsonconfig.Obj(handlerArgs))
diff --git a/server/go/camlistored/sig.go b/server/go/camlistored/sig.go
new file mode 100644
index 000000000..b407329fe
--- /dev/null
+++ b/server/go/camlistored/sig.go
@@ -0,0 +1,41 @@
+/*
+Copyright 2011 Google Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"http"
+	"os"
+
+	"camli/jsonconfig"
+)
+
+type JSONSignHandler struct {
+}
+
+func createJSONSignHandler(conf jsonconfig.Obj) (http.Handler, os.Error) {
+	h := &JSONSignHandler{}
+	//h.Stealth = conf.OptionalBool("stealth", false)
+	if err := conf.Validate(); err != nil {
+		return nil, err
+	}
+	return h, nil
+}
+
+func (h *JSONSignHandler) ServeHTTP(conn http.ResponseWriter, req *http.Request) {
+	// TODO
+}
+
diff --git a/server/go/camlistored/ui.go b/server/go/camlistored/ui.go
index a7ec095e3..41a8df8f7 100644
--- a/server/go/camlistored/ui.go
+++ b/server/go/camlistored/ui.go
@@ -27,15 +27,17 @@ import (
 	"camli/jsonconfig"
 )
 
-var staticFilePattern = regexp.MustCompile(`/([a-z0-9\-\_]+\.(html|js|css|png|jpg|gif))$`)
+var staticFilePattern = regexp.MustCompile(`/static/([a-zA-Z0-9\-\_]+\.(html|js|css|png|jpg|gif))$`)
+var identPattern = regexp.MustCompile(`^[a-zA-Z\_]+$`)
 
 // UIHandler handles serving the UI and discovery JSON.
 type UIHandler struct {
 	// URL prefixes (path or full URL) to the primary blob and
 	// search root.  Only used by the UI and thus necessary if UI
 	// is true.
-	BlobRoot   string
-	SearchRoot string
+	BlobRoot     string
+	SearchRoot   string
+	JSONSignRoot string
 
 	FilesDir string
 }
@@ -47,8 +49,9 @@ func defaultFilesDir() string {
 
 func createUIHandler(conf jsonconfig.Obj) (h http.Handler, err os.Error) {
 	ui := &UIHandler{}
-	ui.BlobRoot = conf.RequiredString("blobRoot")
-	ui.SearchRoot = conf.RequiredString("searchRoot")
+	ui.BlobRoot = conf.OptionalString("blobRoot", "")
+	ui.SearchRoot = conf.OptionalString("searchRoot", "")
+	ui.JSONSignRoot = conf.OptionalString("jsonSignRoot", "")
 	ui.FilesDir = conf.OptionalString("staticFiles", defaultFilesDir())
 	if err = conf.Validate(); err != nil {
 		return
@@ -64,18 +67,18 @@ func createUIHandler(conf jsonconfig.Obj) (h http.Handler, err os.Error) {
 func wantsDiscovery(req *http.Request) bool {
 	return req.Method == "GET" &&
 		(req.Header.Get("Accept") == "text/x-camli-configuration" ||
-		req.FormValue("camli.mode") == "config")
+			req.FormValue("camli.mode") == "config")
 }
 
 func (ui *UIHandler) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
 	rw.Header().Set("Vary", "Accept")
 	switch {
 	case wantsDiscovery(req):
-		ui.serveDiscovery(rw)
+		ui.serveDiscovery(rw, req)
 	default:
-		file := staticFilePattern.FindString(req.URL.Path)
-		if file != "" {
-			file = file[1:]
+		file := ""
+		if m := staticFilePattern.FindStringSubmatch(req.URL.Path); m != nil {
+			file = m[1]
 		} else {
 			file = "index.html"
 		}
@@ -83,10 +86,20 @@ func (ui *UIHandler) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
 	}
 }
 
-func (ui *UIHandler) serveDiscovery(rw http.ResponseWriter) {
+func (ui *UIHandler) serveDiscovery(rw http.ResponseWriter, req *http.Request) {
 	rw.Header().Set("Content-Type", "text/javascript")
-	json.NewEncoder(rw).Encode(map[string]interface{}{
-		"blobRoot": ui.BlobRoot,
-		"searchRoot": ui.SearchRoot,
-	})
+	inCb := false
+	if cb := req.FormValue("cb"); identPattern.MatchString(cb) {
+		fmt.Fprintf(rw, "%s(", cb)
+		inCb = true
+	}
+	bytes, _ := json.Marshal(map[string]interface{}{
+                "blobRoot":   ui.BlobRoot,
+                "searchRoot": ui.SearchRoot,
+                "jsonSignRoot": ui.JSONSignRoot,
+        })
+	rw.Write(bytes)
+	if inCb {
+		rw.Write([]byte{')'})
+	}
 }
diff --git a/server/go/camlistored/ui/index.html b/server/go/camlistored/ui/index.html
index 7137b8f9c..e896a3757 100644
--- a/server/go/camlistored/ui/index.html
+++ b/server/go/camlistored/ui/index.html
@@ -1,7 +1,8 @@
 <html>
 <head>
   <title>Camlistored UI</title>
-  <script src="ui.js"></script>
+  <script src="static/ui.js"></script>
+  <script src="?camli.mode=config&cb=onConfiguration"></script>
 </head>
 <body>
   <h1>Camlistored UI</h1>
diff --git a/server/go/camlistored/ui/ui.js b/server/go/camlistored/ui/ui.js
index 0b3598b63..4401045d4 100644
--- a/server/go/camlistored/ui/ui.js
+++ b/server/go/camlistored/ui/ui.js
@@ -16,6 +16,13 @@ limitations under the License.
 
 var disco = null;
 
+// Method 1 to get discovery information (JSONP style):
+function onConfiguration(conf) {
+    disco = conf;
+    console.log("Got config: " + JSON.stringify(conf));
+}
+
+// Or get configuration info like this:
 function discover() {
     var xhr = new XMLHttpRequest();
     xhr.onreadystatechange = function() {