diff --git a/core/src/main/java/org/springframework/security/ui/preauth/AbstractPreAuthenticatedProcessingFilter.java b/core/src/main/java/org/springframework/security/ui/preauth/AbstractPreAuthenticatedProcessingFilter.java
index bd6cd62dca..457b8a6c66 100755
--- a/core/src/main/java/org/springframework/security/ui/preauth/AbstractPreAuthenticatedProcessingFilter.java
+++ b/core/src/main/java/org/springframework/security/ui/preauth/AbstractPreAuthenticatedProcessingFilter.java
@@ -75,7 +75,7 @@ public abstract class AbstractPreAuthenticatedProcessingFilter extends SpringSec
         Object credentials = getPreAuthenticatedCredentials(httpRequest);
 
         if (logger.isDebugEnabled()) {
-            logger.debug("AbstractPreAuthenticatedProcessingFilter: preAuthenticatedPrincipal=" + principal + ", trying to authenticate");
+            logger.debug("preAuthenticatedPrincipal = " + principal + ", trying to authenticate");
         }
 
         try {