diff --git a/config/src/main/java/org/springframework/security/config/annotation/authentication/configuration/AuthenticationConfiguration.java b/config/src/main/java/org/springframework/security/config/annotation/authentication/configuration/AuthenticationConfiguration.java
index 2959b528cd..ee7c046191 100644
--- a/config/src/main/java/org/springframework/security/config/annotation/authentication/configuration/AuthenticationConfiguration.java
+++ b/config/src/main/java/org/springframework/security/config/annotation/authentication/configuration/AuthenticationConfiguration.java
@@ -31,11 +31,13 @@ import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Import;
 import org.springframework.core.annotation.AnnotationAwareOrderComparator;
 import org.springframework.security.authentication.AuthenticationManager;
 import org.springframework.security.config.annotation.ObjectPostProcessor;
 import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
 import org.springframework.security.config.annotation.authentication.configurers.GlobalAuthenticationConfigurerAdapter;
+import org.springframework.security.config.annotation.configuration.ObjectPostProcessorConfiguration;
 import org.springframework.security.core.Authentication;
 import org.springframework.security.core.AuthenticationException;
 import org.springframework.util.Assert;
@@ -48,6 +50,7 @@ import org.springframework.util.Assert;
  *
  */
 @Configuration
+@Import(ObjectPostProcessorConfiguration.class)
 public class AuthenticationConfiguration {
 
 	private AtomicBoolean buildingAuthenticationManager = new AtomicBoolean();
diff --git a/config/src/main/java/org/springframework/security/config/annotation/method/configuration/EnableGlobalMethodSecurity.java b/config/src/main/java/org/springframework/security/config/annotation/method/configuration/EnableGlobalMethodSecurity.java
index defd6bde07..93b5a38e2a 100644
--- a/config/src/main/java/org/springframework/security/config/annotation/method/configuration/EnableGlobalMethodSecurity.java
+++ b/config/src/main/java/org/springframework/security/config/annotation/method/configuration/EnableGlobalMethodSecurity.java
@@ -25,7 +25,6 @@ import org.springframework.context.annotation.Import;
 import org.springframework.core.Ordered;
 import org.springframework.security.access.annotation.Secured;
 import org.springframework.security.config.annotation.authentication.configuration.EnableGlobalAuthentication;
-import org.springframework.security.config.annotation.configuration.ObjectPostProcessorConfiguration;
 
 /**
  * <p>
@@ -45,7 +44,7 @@ import org.springframework.security.config.annotation.configuration.ObjectPostPr
 @Retention(value = java.lang.annotation.RetentionPolicy.RUNTIME)
 @Target(value = { java.lang.annotation.ElementType.TYPE })
 @Documented
-@Import({ GlobalMethodSecuritySelector.class, ObjectPostProcessorConfiguration.class })
+@Import({ GlobalMethodSecuritySelector.class })
 @EnableGlobalAuthentication
 @Configuration
 public @interface EnableGlobalMethodSecurity {
diff --git a/config/src/main/java/org/springframework/security/config/annotation/method/configuration/GlobalMethodSecurityConfiguration.java b/config/src/main/java/org/springframework/security/config/annotation/method/configuration/GlobalMethodSecurityConfiguration.java
index 78ed82e76e..c541aff573 100644
--- a/config/src/main/java/org/springframework/security/config/annotation/method/configuration/GlobalMethodSecurityConfiguration.java
+++ b/config/src/main/java/org/springframework/security/config/annotation/method/configuration/GlobalMethodSecurityConfiguration.java
@@ -49,7 +49,6 @@ import org.springframework.security.access.hierarchicalroles.RoleHierarchy;
 import org.springframework.security.access.intercept.AfterInvocationManager;
 import org.springframework.security.access.intercept.AfterInvocationProviderManager;
 import org.springframework.security.access.intercept.RunAsManager;
-import org.springframework.security.access.intercept.RunAsManagerImpl;
 import org.springframework.security.access.intercept.aopalliance.MethodSecurityInterceptor;
 import org.springframework.security.access.intercept.aspectj.AspectJMethodSecurityInterceptor;
 import org.springframework.security.access.method.DelegatingMethodSecurityMetadataSource;
diff --git a/config/src/main/java/org/springframework/security/config/annotation/web/configuration/EnableWebSecurity.java b/config/src/main/java/org/springframework/security/config/annotation/web/configuration/EnableWebSecurity.java
index baa0e3c7c3..1b5067c576 100644
--- a/config/src/main/java/org/springframework/security/config/annotation/web/configuration/EnableWebSecurity.java
+++ b/config/src/main/java/org/springframework/security/config/annotation/web/configuration/EnableWebSecurity.java
@@ -22,7 +22,6 @@ import java.lang.annotation.Target;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Import;
 import org.springframework.security.config.annotation.authentication.configuration.EnableGlobalAuthentication;
-import org.springframework.security.config.annotation.configuration.ObjectPostProcessorConfiguration;
 import org.springframework.security.config.annotation.web.WebSecurityConfigurer;
 
 /**
@@ -73,7 +72,7 @@ import org.springframework.security.config.annotation.web.WebSecurityConfigurer;
 @Retention(value = java.lang.annotation.RetentionPolicy.RUNTIME)
 @Target(value = { java.lang.annotation.ElementType.TYPE })
 @Documented
-@Import({ WebSecurityConfiguration.class, ObjectPostProcessorConfiguration.class,
+@Import({ WebSecurityConfiguration.class,
 		SpringWebMvcImportSelector.class })
 @EnableGlobalAuthentication
 @Configuration
diff --git a/config/src/test/java/org/springframework/security/config/annotation/authentication/configuration/EnableGlobalAuthenticationTests.java b/config/src/test/java/org/springframework/security/config/annotation/authentication/configuration/EnableGlobalAuthenticationTests.java
new file mode 100644
index 0000000000..75e7eef385
--- /dev/null
+++ b/config/src/test/java/org/springframework/security/config/annotation/authentication/configuration/EnableGlobalAuthenticationTests.java
@@ -0,0 +1,53 @@
+/*
+ * Copyright 2002-2016 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.config.annotation.authentication.configuration;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+/**
+ *
+ * @author Rob Winch
+ *
+ */
+@RunWith(SpringJUnit4ClassRunner.class)
+public class EnableGlobalAuthenticationTests {
+	@Autowired
+	AuthenticationConfiguration auth;
+
+	// gh-4086
+	@Test
+	public void authenticationConfigurationWhenGetAuthenticationManagerThenNotNull() throws Exception {
+		assertThat(auth.getAuthenticationManager()).isNotNull();
+	}
+
+	@Configuration
+	@EnableGlobalAuthentication
+	static class Config {
+
+		@Autowired
+		public void configureGlobal(AuthenticationManagerBuilder auth) throws Exception {
+			auth.inMemoryAuthentication().withUser("user").password("password").roles("USER");
+		}
+	}
+
+}