Index: org/apache/catalina/authenticator/AuthenticatorBase.java
===================================================================
--- org/apache/catalina/authenticator/AuthenticatorBase.java	(revision 831814)
+++ org/apache/catalina/authenticator/AuthenticatorBase.java	(working copy)
@@ -579,7 +579,7 @@
         bytes = getDigest().digest(bytes);
 
         // Render the result as a String of hexadecimal digits
-        StringBuffer result = new StringBuffer();
+        StringBuilder result = new StringBuilder();
         for (int i = 0; i < bytes.length; i++) {
             byte b1 = (byte) ((bytes[i] & 0xf0) >> 4);
             byte b2 = (byte) (bytes[i] & 0x0f);
Index: org/apache/catalina/authenticator/FormAuthenticator.java
===================================================================
--- org/apache/catalina/authenticator/FormAuthenticator.java	(revision 831814)
+++ org/apache/catalina/authenticator/FormAuthenticator.java	(working copy)
@@ -530,7 +530,7 @@
             (SavedRequest) session.getNote(Constants.FORM_REQUEST_NOTE);
         if (saved == null)
             return (null);
-        StringBuffer sb = new StringBuffer(saved.getRequestURI());
+        StringBuilder sb = new StringBuilder(saved.getRequestURI());
         if (saved.getQueryString() != null) {
             sb.append('?');
             sb.append(saved.getQueryString());
Index: org/apache/catalina/authenticator/SingleSignOn.java
===================================================================
--- org/apache/catalina/authenticator/SingleSignOn.java	(revision 831814)
+++ org/apache/catalina/authenticator/SingleSignOn.java	(working copy)
@@ -431,7 +431,7 @@
      */
     public String toString() {
 
-        StringBuffer sb = new StringBuffer("SingleSignOn[");
+        StringBuilder sb = new StringBuilder("SingleSignOn[");
         if (container == null )
             sb.append("Container is null");
         else