diff --git a/CHANGES.txt b/CHANGES.txt
index 175de25b2b1..fb64c2e962f 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -59,6 +59,9 @@ New Features
     In the process, an init(NamedList) method was added to QueryResponseWriter
     which works the same way as SolrRequestHandler.
     (Bertrand Delacretaz / SOLR-49 / hossman)
+28. json.wrf parameter adds a wrapper-function around the JSON response,
+    useful in AJAX with dynamic script tags for specifying a JavaScript
+    callback function. (Bertrand Delacretaz via yonik, SOLR-56)
     
 Changes in runtime behavior
  1. classes reorganized into different packages, package names changed to Apache
diff --git a/src/java/org/apache/solr/request/JSONResponseWriter.java b/src/java/org/apache/solr/request/JSONResponseWriter.java
index 7ef473225f9..e1bbeec6791 100644
--- a/src/java/org/apache/solr/request/JSONResponseWriter.java
+++ b/src/java/org/apache/solr/request/JSONResponseWriter.java
@@ -41,17 +41,20 @@ class JSONWriter extends TextResponseWriter {
   private Calendar cal;
 
   private String namedListStyle;
+  private String wrapperFunction;
 
   private static final String JSON_NL_STYLE="json.nl";
   private static final String JSON_NL_MAP="map";
   private static final String JSON_NL_ARROFARR="arrarr";
   private static final String JSON_NL_ARROFMAP="arrmap";
+  private static final String JSON_WRAPPER_FUNCTION="json.wrf";
 
 
   public JSONWriter(Writer writer, SolrQueryRequest req, SolrQueryResponse rsp) {
     super(writer, req, rsp);
     namedListStyle = req.getParam(JSON_NL_STYLE);
     namedListStyle = namedListStyle==null ? JSON_NL_MAP : namedListStyle.intern();
+    wrapperFunction = req.getParam(JSON_WRAPPER_FUNCTION);
   }
 
   public void writeResponse() throws IOException {
@@ -65,7 +68,13 @@ class JSONWriter extends TextResponseWriter {
     if (nl.size()>1 && nl.getVal(1) instanceof DocList && nl.getName(1)==null) {
       nl.setName(1,"response");
     }
+    if(wrapperFunction!=null) {
+        writer.write(wrapperFunction + "(");
+    }
     writeNamedList(null, nl);
+    if(wrapperFunction!=null) {
+        writer.write(")");
+    }
   }
 
   protected void writeKey(String fname, boolean needsEscaping) throws IOException {