--- a/lib/js/urweb.js	Tue May 27 21:15:53 2014 -0400
+++ b/lib/js/urweb.js	Tue May 27 21:38:01 2014 -0400
@@ -1009,8 +1009,6 @@
     if (suspendScripts)
         return;
 
-    var span = document.createElement("span");
-    addNode(span);
     var ms = maySuspend;
     maySuspend = false;
     try {
@@ -1020,7 +1018,11 @@
         throw e;
     }
     maySuspend = ms;
-    setInnerHTML(span, html);
+    if (html != "") {
+        var span = document.createElement("span");
+        addNode(span);
+        setInnerHTML(span, html);
+    }
 }
 
 function input(x, s, recreate, type, name) {
@@ -1111,7 +1113,7 @@
     return x;
 }
 
-function dynClass(html, s_class, s_style) {
+function dynClass(pnode, html, s_class, s_style) {
     if (suspendScripts)
         return;
 
@@ -1119,7 +1121,7 @@
     html = flatten(htmlCls, html);
     htmlCls = htmlCls.v;
 
-    var dummy = document.createElement("body");
+    var dummy = document.createElement(pnode);
     suspendScripts = true;
     dummy.innerHTML = html;
     suspendScripts = false;
@@ -1150,23 +1152,23 @@
 
     if (s_style) {
         var htmlCls2 = s_class ? null : htmlCls;
-        var x = document.createElement("script");
-        x.dead = false;
-        x.signal = s_style;
-        x.sources = null;
-        x.closures = htmlCls2;
+        var y = document.createElement("script");
+        y.dead = false;
+        y.signal = s_style;
+        y.sources = null;
+        y.closures = htmlCls2;
 
-        x.recreate = function(v) {
-            for (var ls = x.closures; ls != htmlCls2; ls = ls.next)
+        y.recreate = function(v) {
+            for (var ls = y.closures; ls != htmlCls2; ls = ls.next)
                 freeClosure(ls.data);
 
             var cls = {v : null};
             html.style.cssText = flatten(cls, v);
-	    x.closures = concat(cls.v, htmlCls2);
+	    y.closures = concat(cls.v, htmlCls2);
         }
 
-        html.appendChild(x);
-        populate(x);
+        html.appendChild(y);
+        populate(y);
     }
 }
 
@@ -1940,6 +1942,19 @@
 }
 
 
+// Attribute name blessing
+
+function blessData(s) {
+    for (var i = 0; i < s.length; ++i) {
+        var c = s[i];
+        if (!isAlnum(c) && c != '-' && c != '_')
+            er("Disallowed character in data-* attribute name");
+    }
+
+    return s;
+}
+
+
 // CSS validation
 
 function atom(s) {