diff --git a/js/Name.js b/js/Name.js
index a89ea21..1f1f843 100644
--- a/js/Name.js
+++ b/js/Name.js
@@ -177,6 +177,27 @@
     return result;
 }
 
+/*
+ * The "file name" in a name is the last component that isn't blank and doesn't start with one of the
+ *   special marker octets (for version, etc.).  Return the index in this.components of
+ *   the file name, or -1 if not found.
+ */
+Name.prototype.indexOfFileName = function() {
+    for (var i = this.components.length - 1; i >= 0; --i) {
+        var component = this.components[i];
+        if (component.length <= 0)
+            continue;
+        
+        if (component[0] == 0 || component[0] == 0xC0 || component[0] == 0xC1 || 
+            (component[0] >= 0xF5 && component[0] <= 0xFF))
+            continue;
+        
+        return i;
+    }
+    
+    return -1;
+}
+
 /**
  * Return component as an escaped string according to "CCNx URI Scheme".
  * We can't use encodeURIComponent because that doesn't encode all the characters we want to.
diff --git a/js/ccnxProtocol/components/ccnxProtocolService.js b/js/ccnxProtocol/components/ccnxProtocolService.js
index 5308fdd..c57d94a 100644
--- a/js/ccnxProtocol/components/ccnxProtocolService.js
+++ b/js/ccnxProtocol/components/ccnxProtocolService.js
@@ -211,22 +211,13 @@
  *   for a recognized file name extension, and return an object with properties contentType and charset.
  */
 function getNameContentTypeAndCharset(name) {
-    var filename = "";
-    for (var i = name.components.length - 1; i >= 0; --i) {
-        var component = name.components[i];
-        if (component.length <= 0)
-            continue;
-        
-        // Skip special components which just may have ".gif", etc.
-        if (component[0] == 0 || component[0] == 0xC0 || component[0] == 0xC1 || 
-            (component[0] >= 0xF5 && component[0] <= 0xFF))
-            continue;
-        
-        filename = DataUtils.toString(component).toLowerCase();
-        break;
-    }
+    var iFileName = name.indexOfFileName();
+    if (iFileName < 0)
+        // Get the default mime type.
+        return MimeTypes.getContentTypeAndCharset("");
     
-    return MimeTypes.getContentTypeAndCharset(filename);
+    return MimeTypes.getContentTypeAndCharset
+        (DataUtils.toString(name.components[iFileName]).toLowerCase());
 }
 
 /*