diff --git a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/AuthenticationManagerConfiguration.java b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/AuthenticationManagerConfiguration.java
index 11dbad4ca85..74cd06b8a7b 100644
--- a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/AuthenticationManagerConfiguration.java
+++ b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/AuthenticationManagerConfiguration.java
@@ -42,6 +42,7 @@ import org.springframework.security.config.annotation.SecurityConfigurer;
 import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
 import org.springframework.security.config.annotation.authentication.configuration.AuthenticationConfiguration;
 import org.springframework.security.config.annotation.authentication.configurers.GlobalAuthenticationConfigurerAdapter;
+import org.springframework.security.config.annotation.authentication.configurers.provisioning.InMemoryUserDetailsManagerConfigurer;
 import org.springframework.stereotype.Component;
 
 /**
@@ -138,22 +139,59 @@ public class AuthenticationManagerConfiguration {
 
 		@Override
 		public void init(AuthenticationManagerBuilder auth) throws Exception {
-			if (auth.isConfigured()) {
-				return;
+			auth.apply(new DefaultingInMemoryUserDetailsManagerConfigurer(this.security));
+		}
+
+		/**
+		 * This is necessary to delay adding the default user.
+		 *
+		 * <ul>
+		 * <li>A GlobalAuthenticationConfigurerAdapter will initialize the
+		 * AuthenticationManagerBuilder with a Configurer which will be after any
+		 * GlobalAuthenticationConfigurerAdapter</li>
+		 * <li>BootDefaultingAuthenticationConfigurerAdapter will be invoked after all
+		 * GlobalAuthenticationConfigurerAdapter, but before the Configurers that were
+		 * added by other GlobalAuthenticationConfigurerAdapter instances</li>
+		 * <li>BootDefaultingAuthenticationConfigurerAdapter will add
+		 * DefaultingInMemoryUserDetailsManagerConfigurer after all Configurer instances</li>
+		 * <li>All init methods will be invoked</li>
+		 * <li>All configure methods will be invoked which is where the
+		 * AuthenticationProvider instances are setup</li>
+		 * <li>If no AuthenticationProviders were provided,
+		 * DefaultingInMemoryUserDetailsManagerConfigurer will default the value</li>
+		 * </ul>
+		 *
+		 * @author Rob Winch
+		 */
+		private static class DefaultingInMemoryUserDetailsManagerConfigurer extends
+				InMemoryUserDetailsManagerConfigurer<AuthenticationManagerBuilder> {
+			private final SecurityProperties security;
+
+			public DefaultingInMemoryUserDetailsManagerConfigurer(
+					SecurityProperties security) {
+				this.security = security;
 			}
 
-			User user = this.security.getUser();
-			if (user.isDefaultPassword()) {
-				logger.info("\n\nUsing default security password: " + user.getPassword()
-						+ "\n");
+			@Override
+			public void configure(AuthenticationManagerBuilder auth) throws Exception {
+				if (auth.isConfigured()) {
+					return;
+				}
+
+				User user = this.security.getUser();
+				if (user.isDefaultPassword()) {
+					logger.info("\n\nUsing default security password: "
+							+ user.getPassword() + "\n");
+				}
+
+				Set<String> roles = new LinkedHashSet<String>(user.getRole());
+				withUser(user.getName()).password(user.getPassword()).roles(
+						roles.toArray(new String[roles.size()]));
+
+				super.configure(auth);
 			}
 
-			Set<String> roles = new LinkedHashSet<String>(user.getRole());
-			auth.inMemoryAuthentication().withUser(user.getName())
-					.password(user.getPassword())
-					.roles(roles.toArray(new String[roles.size()]));
 		}
 
 	}
-
-}
+}
\ No newline at end of file
diff --git a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/security/SecurityAutoConfigurationTests.java b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/security/SecurityAutoConfigurationTests.java
index b662ae7e1bb..f743f6da58c 100644
--- a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/security/SecurityAutoConfigurationTests.java
+++ b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/security/SecurityAutoConfigurationTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2014 the original author or authors.
+ * Copyright 2012-2015 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.
@@ -256,6 +256,49 @@ public class SecurityAutoConfigurationTests {
 		assertNotNull(this.context.getBean(JpaTransactionManager.class));
 	}
 
+	@Test
+	public void testDefaultUsernamePassword() throws Exception {
+		this.context = new AnnotationConfigWebApplicationContext();
+		this.context.setServletContext(new MockServletContext());
+
+		this.context.register(SecurityAutoConfiguration.class,
+				ServerPropertiesAutoConfiguration.class);
+		this.context.refresh();
+
+		SecurityProperties security = this.context.getBean(SecurityProperties.class);
+		AuthenticationManager manager = this.context.getBean(AuthenticationManager.class);
+
+		UsernamePasswordAuthenticationToken token = new UsernamePasswordAuthenticationToken(
+				security.getUser().getName(), security.getUser().getPassword());
+		assertNotNull(manager.authenticate(token));
+	}
+
+	@Test
+	public void testCustomAuthenticationDoesNotAuthenticateWithBootSecurityUser()
+			throws Exception {
+		this.context = new AnnotationConfigWebApplicationContext();
+		this.context.setServletContext(new MockServletContext());
+
+		this.context.register(AuthenticationManagerCustomizer.class,
+				SecurityAutoConfiguration.class, ServerPropertiesAutoConfiguration.class);
+		this.context.refresh();
+
+		SecurityProperties security = this.context.getBean(SecurityProperties.class);
+		AuthenticationManager manager = this.context.getBean(AuthenticationManager.class);
+
+		UsernamePasswordAuthenticationToken token = new UsernamePasswordAuthenticationToken(
+				security.getUser().getName(), security.getUser().getPassword());
+		try {
+			manager.authenticate(token);
+			fail("Expected Exception");
+		}
+		catch (AuthenticationException success) {
+		}
+
+		token = new UsernamePasswordAuthenticationToken("foo", "bar");
+		assertNotNull(manager.authenticate(token));
+	}
+
 	private static final class AuthenticationListener implements
 			ApplicationListener<AbstractAuthenticationEvent> {