diff -r efd9c589177a -r c0b4a8b5a012 toolkit/javascript/d3/src/core/selection-enter-select.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/javascript/d3/src/core/selection-enter-select.js	Thu Apr 10 14:20:23 2014 +0200
@@ -0,0 +1,24 @@
+d3_selection_enterPrototype.select = function(selector) {
+  var subgroups = [],
+      subgroup,
+      subnode,
+      upgroup,
+      group,
+      node;
+
+  for (var j = -1, m = this.length; ++j < m;) {
+    upgroup = (group = this[j]).update;
+    subgroups.push(subgroup = []);
+    subgroup.parentNode = group.parentNode;
+    for (var i = -1, n = group.length; ++i < n;) {
+      if (node = group[i]) {
+        subgroup.push(upgroup[i] = subnode = selector.call(group.parentNode, node.__data__, i));
+        subnode.__data__ = node.__data__;
+      } else {
+        subgroup.push(null);
+      }
+    }
+  }
+
+  return d3_selection(subgroups);
+};