diff --git a/core/src/main/java/org/springframework/security/authentication/AuthenticationServiceException.java b/core/src/main/java/org/springframework/security/authentication/AuthenticationServiceException.java
index 6a6de158ed..950fd4586f 100644
--- a/core/src/main/java/org/springframework/security/authentication/AuthenticationServiceException.java
+++ b/core/src/main/java/org/springframework/security/authentication/AuthenticationServiceException.java
@@ -23,6 +23,7 @@ import org.springframework.security.core.AuthenticationException;
  * This might be thrown if a backend authentication repository is  unavailable, for example.
  *
  * @author Ben Alex
+ * @see InternalAuthenticationServiceException
  */
 public class AuthenticationServiceException extends AuthenticationException {
     //~ Constructors ===================================================================================================
diff --git a/core/src/main/java/org/springframework/security/authentication/InternalAuthenticationServiceException.java b/core/src/main/java/org/springframework/security/authentication/InternalAuthenticationServiceException.java
new file mode 100644
index 0000000000..648f3b5291
--- /dev/null
+++ b/core/src/main/java/org/springframework/security/authentication/InternalAuthenticationServiceException.java
@@ -0,0 +1,40 @@
+/*
+ * Copyright 2002-2012 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
+ * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations under the License.
+ */
+package org.springframework.security.authentication;
+
+/**
+ * <p>
+ * Thrown if an authentication request could not be processed due to a system problem that occurred internally. It
+ * differs from {@link AuthenticationServiceException} in that it would not be thrown if an external system has an
+ * internal error or failure. This ensures that we can handle errors that are within our control distinctly from errors
+ * of other systems. The advantage to this distinction is that the unrusted external system should not be able to fill
+ * up logs and cause excessive IO. However, an internal system should report errors.
+ * </p>
+ * <p>
+ * This might be thrown if a backend authentication repository is unavailable, for example. However, it would not be
+ * thrown in the event that an error occurred when validating an OpenID response with an OpenID Provider.
+ * </p>
+ *
+ * @author Rob Winch
+ *
+ */
+public class InternalAuthenticationServiceException extends AuthenticationServiceException {
+
+    public InternalAuthenticationServiceException(String message, Throwable cause) {
+        super(message, cause);
+    }
+
+    public InternalAuthenticationServiceException(String message) {
+        super(message);
+    }
+}
\ No newline at end of file
diff --git a/ldap/src/main/java/org/springframework/security/ldap/authentication/LdapAuthenticationProvider.java b/ldap/src/main/java/org/springframework/security/ldap/authentication/LdapAuthenticationProvider.java
index e205c85964..10f5976690 100644
--- a/ldap/src/main/java/org/springframework/security/ldap/authentication/LdapAuthenticationProvider.java
+++ b/ldap/src/main/java/org/springframework/security/ldap/authentication/LdapAuthenticationProvider.java
@@ -17,8 +17,8 @@ package org.springframework.security.ldap.authentication;
 
 import org.springframework.ldap.NamingException;
 import org.springframework.ldap.core.DirContextOperations;
-import org.springframework.security.authentication.AuthenticationServiceException;
 import org.springframework.security.authentication.BadCredentialsException;
+import org.springframework.security.authentication.InternalAuthenticationServiceException;
 import org.springframework.security.authentication.LockedException;
 import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
 import org.springframework.security.core.GrantedAuthority;
@@ -188,7 +188,7 @@ public class LdapAuthenticationProvider extends AbstractLdapAuthenticationProvid
                 throw notFound;
             }
         } catch (NamingException ldapAccessFailure) {
-            throw new AuthenticationServiceException(ldapAccessFailure.getMessage(), ldapAccessFailure);
+            throw new InternalAuthenticationServiceException(ldapAccessFailure.getMessage(), ldapAccessFailure);
         }
     }
 
diff --git a/ldap/src/test/java/org/springframework/security/ldap/authentication/LdapAuthenticationProviderTests.java b/ldap/src/test/java/org/springframework/security/ldap/authentication/LdapAuthenticationProviderTests.java
index 63aa441a23..8ec29e2940 100644
--- a/ldap/src/test/java/org/springframework/security/ldap/authentication/LdapAuthenticationProviderTests.java
+++ b/ldap/src/test/java/org/springframework/security/ldap/authentication/LdapAuthenticationProviderTests.java
@@ -21,10 +21,12 @@ import static org.mockito.Mockito.*;
 import java.util.*;
 
 import org.junit.Test;
+import org.springframework.ldap.CommunicationException;
 import org.springframework.ldap.core.DirContextAdapter;
 import org.springframework.ldap.core.DirContextOperations;
 import org.springframework.ldap.core.DistinguishedName;
 import org.springframework.security.authentication.BadCredentialsException;
+import org.springframework.security.authentication.InternalAuthenticationServiceException;
 import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
 import org.springframework.security.core.Authentication;
 import org.springframework.security.core.GrantedAuthority;
@@ -39,6 +41,7 @@ import org.springframework.security.ldap.userdetails.LdapUserDetailsMapper;
  * Tests {@link LdapAuthenticationProvider}.
  *
  * @author Luke Taylor
+ * @author Rob Winch
  */
 public class LdapAuthenticationProviderTests {
 
@@ -147,6 +150,22 @@ public class LdapAuthenticationProviderTests {
         assertTrue(AuthorityUtils.authorityListToSet(user.getAuthorities()).contains("ROLE_FROM_ENTRY"));
     }
 
+    @Test
+    public void authenticateWithNamingException() {
+        UsernamePasswordAuthenticationToken authRequest = new UsernamePasswordAuthenticationToken("ben", "benspassword");
+        LdapAuthenticator mockAuthenticator = mock(LdapAuthenticator.class);
+        CommunicationException expectedCause = new CommunicationException(new javax.naming.CommunicationException());
+        when(mockAuthenticator.authenticate(authRequest)).thenThrow(expectedCause);
+
+        LdapAuthenticationProvider ldapProvider = new LdapAuthenticationProvider(mockAuthenticator);
+        try {
+            ldapProvider.authenticate(authRequest);
+            fail("Expected Exception");
+        } catch(InternalAuthenticationServiceException success) {
+            assertSame(expectedCause, success.getCause());
+        }
+    }
+
     //~ Inner Classes ==================================================================================================
 
     class MockAuthenticator implements LdapAuthenticator {
diff --git a/web/src/main/java/org/springframework/security/web/authentication/AbstractAuthenticationProcessingFilter.java b/web/src/main/java/org/springframework/security/web/authentication/AbstractAuthenticationProcessingFilter.java
index 1f94305519..a2db490781 100644
--- a/web/src/main/java/org/springframework/security/web/authentication/AbstractAuthenticationProcessingFilter.java
+++ b/web/src/main/java/org/springframework/security/web/authentication/AbstractAuthenticationProcessingFilter.java
@@ -31,6 +31,7 @@ import org.springframework.context.MessageSourceAware;
 import org.springframework.context.support.MessageSourceAccessor;
 import org.springframework.security.authentication.AuthenticationDetailsSource;
 import org.springframework.security.authentication.AuthenticationManager;
+import org.springframework.security.authentication.InternalAuthenticationServiceException;
 import org.springframework.security.authentication.event.InteractiveAuthenticationSuccessEvent;
 import org.springframework.security.core.Authentication;
 import org.springframework.security.core.AuthenticationException;
@@ -197,6 +198,11 @@ public abstract class AbstractAuthenticationProcessingFilter extends GenericFilt
                 return;
             }
             sessionStrategy.onAuthentication(authResult, request, response);
+        } catch(InternalAuthenticationServiceException failed) {
+            logger.error("An internal error occurred while trying to authenticate the user.", failed);
+            unsuccessfulAuthentication(request, response, failed);
+
+            return;
         }
         catch (AuthenticationException failed) {
             // Authentication failed
diff --git a/web/src/test/java/org/springframework/security/web/authentication/AbstractAuthenticationProcessingFilterTests.java b/web/src/test/java/org/springframework/security/web/authentication/AbstractAuthenticationProcessingFilterTests.java
index 693a24d1cb..21be453b4e 100644
--- a/web/src/test/java/org/springframework/security/web/authentication/AbstractAuthenticationProcessingFilterTests.java
+++ b/web/src/test/java/org/springframework/security/web/authentication/AbstractAuthenticationProcessingFilterTests.java
@@ -18,6 +18,7 @@ package org.springframework.security.web.authentication;
 import static org.junit.Assert.*;
 import static org.mockito.Mockito.*;
 
+import org.apache.commons.logging.Log;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
@@ -26,6 +27,7 @@ import org.springframework.mock.web.MockHttpServletRequest;
 import org.springframework.mock.web.MockHttpServletResponse;
 import org.springframework.security.authentication.AuthenticationManager;
 import org.springframework.security.authentication.BadCredentialsException;
+import org.springframework.security.authentication.InternalAuthenticationServiceException;
 import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
 import org.springframework.security.core.Authentication;
 import org.springframework.security.core.AuthenticationException;
@@ -33,6 +35,7 @@ import org.springframework.security.core.authority.AuthorityUtils;
 import org.springframework.security.core.context.SecurityContextHolder;
 import org.springframework.security.web.authentication.rememberme.TokenBasedRememberMeServices;
 import org.springframework.security.web.authentication.session.SessionAuthenticationStrategy;
+import org.springframework.test.util.ReflectionTestUtils;
 
 import javax.servlet.FilterChain;
 import javax.servlet.ServletException;
@@ -49,6 +52,7 @@ import java.io.IOException;
  *
  * @author Ben Alex
  * @author Luke Taylor
+ * @author Rob Winch
  */
 @SuppressWarnings("deprecation")
 public class AbstractAuthenticationProcessingFilterTests {
@@ -352,6 +356,28 @@ public class AbstractAuthenticationProcessingFilterTests {
         assertEquals(HttpServletResponse.SC_UNAUTHORIZED, response.getStatus());
     }
 
+    /**
+     * SEC-1919
+     */
+    @Test
+    public void loginErrorWithInternAuthenticationServiceExceptionLogsError() throws Exception {
+        MockHttpServletRequest request = createMockAuthenticationRequest();
+
+        MockFilterChain chain = new MockFilterChain(true);
+        MockHttpServletResponse response = new MockHttpServletResponse();
+
+        Log logger = mock(Log.class);
+        MockAuthenticationFilter filter = new MockAuthenticationFilter(false);
+        ReflectionTestUtils.setField(filter, "logger", logger);
+        filter.exceptionToThrow = new InternalAuthenticationServiceException("Mock requested to do so");
+        successHandler.setDefaultTargetUrl("http://monkeymachine.co.uk/");
+        filter.setAuthenticationSuccessHandler(successHandler);
+
+        filter.doFilter(request, response, chain);
+
+        verify(logger).error(anyString(), eq(filter.exceptionToThrow));
+        assertEquals(HttpServletResponse.SC_UNAUTHORIZED, response.getStatus());
+    }
 
     //~ Inner Classes ==================================================================================================