diff --git a/cas-client-core/src/main/java/org/jasig/cas/client/authentication/DefaultGatewayResolverImpl.java b/cas-client-core/src/main/java/org/jasig/cas/client/authentication/DefaultGatewayResolverImpl.java
index d0d2475..ca4c0c8 100644
--- a/cas-client-core/src/main/java/org/jasig/cas/client/authentication/DefaultGatewayResolverImpl.java
+++ b/cas-client-core/src/main/java/org/jasig/cas/client/authentication/DefaultGatewayResolverImpl.java
@@ -33,7 +33,6 @@ public final class DefaultGatewayResolverImpl implements GatewayResolver {
         }
 
         final boolean result = session.getAttribute(CONST_CAS_GATEWAY) != null;
-        session.removeAttribute(CONST_CAS_GATEWAY);
         return result;
     }
 
diff --git a/cas-client-core/src/test/java/org/jasig/cas/client/authentication/AuthenticationFilterTests.java b/cas-client-core/src/test/java/org/jasig/cas/client/authentication/AuthenticationFilterTests.java
index 48479a5..742a5cf 100644
--- a/cas-client-core/src/test/java/org/jasig/cas/client/authentication/AuthenticationFilterTests.java
+++ b/cas-client-core/src/test/java/org/jasig/cas/client/authentication/AuthenticationFilterTests.java
@@ -177,8 +177,13 @@ public final class AuthenticationFilterTests {
 
         final MockHttpServletResponse response2 = new MockHttpServletResponse();
         this.filter.doFilter(request, response2, filterChain);
-        assertNull(session.getAttribute(DefaultGatewayResolverImpl.CONST_CAS_GATEWAY));
+        assertNotNull(session.getAttribute(DefaultGatewayResolverImpl.CONST_CAS_GATEWAY));
         assertNull(response2.getRedirectedUrl());
+		
+        final MockHttpServletResponse response3 = new MockHttpServletResponse();
+        this.filter.doFilter(request, response3, filterChain);
+        assertNotNull(session.getAttribute(DefaultGatewayResolverImpl.CONST_CAS_GATEWAY));
+        assertNull(response3.getRedirectedUrl());
     }
 
     @Test
diff --git a/cas-client-core/src/test/java/org/jasig/cas/client/authentication/DefaultGatewayResolverImplTests.java b/cas-client-core/src/test/java/org/jasig/cas/client/authentication/DefaultGatewayResolverImplTests.java
new file mode 100644
index 0000000..f8e75e6
--- /dev/null
+++ b/cas-client-core/src/test/java/org/jasig/cas/client/authentication/DefaultGatewayResolverImplTests.java
@@ -0,0 +1,72 @@
+/*
+ * Licensed to Jasig under one or more contributor license
+ * agreements. See the NOTICE file distributed with this work
+ * for additional information regarding copyright ownership.
+ * Jasig licenses this file to you 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 the following location:
+ *
+ *   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.jasig.cas.client.authentication;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import org.junit.Before;
+import org.junit.Test;
+import org.springframework.mock.web.MockHttpServletRequest;
+import org.springframework.mock.web.MockHttpServletResponse;
+import org.springframework.mock.web.MockHttpSession;
+
+public class DefaultGatewayResolverImplTests {
+
+    private DefaultGatewayResolverImpl resolver;
+
+    @Before
+    public void setUp() throws Exception {
+        this.resolver = new DefaultGatewayResolverImpl();
+    }
+
+    @Test
+    public void testReentrancy() throws Exception {
+        final MockHttpServletRequest request1 = new MockHttpServletRequest();
+        assertFalse(this.resolver.hasGatewayedAlready(request1, "foo"));
+        assertFalse(this.resolver.hasGatewayedAlready(request1, "foo"));
+        assertEquals("foo", this.resolver.storeGatewayInformation(request1, "foo"));
+        assertEquals("foo", this.resolver.storeGatewayInformation(request1, "foo"));
+        assertTrue(this.resolver.hasGatewayedAlready(request1, "foo"));
+        assertTrue(this.resolver.hasGatewayedAlready(request1, "foo"));
+	}
+	
+    @Test
+    public void testSessionConcurrency() throws Exception {
+        final MockHttpSession session = new MockHttpSession();
+        final MockHttpServletRequest request1 = new MockHttpServletRequest();
+        final MockHttpServletRequest request2 = new MockHttpServletRequest();
+		request1.setSession(session);
+		request2.setSession(session);
+
+        assertFalse(this.resolver.hasGatewayedAlready(request1, "abc"));
+        assertFalse(this.resolver.hasGatewayedAlready(request2, "def"));
+		
+        assertEquals("abc", this.resolver.storeGatewayInformation(request1, "abc"));
+		
+        assertTrue(this.resolver.hasGatewayedAlready(request2, "def"));
+        assertTrue(this.resolver.hasGatewayedAlready(request1, "abc"));
+		
+        assertEquals("def", this.resolver.storeGatewayInformation(request2, "def"));
+
+		assertTrue(this.resolver.hasGatewayedAlready(request1, "abc"));
+        assertTrue(this.resolver.hasGatewayedAlready(request2, "def"));
+
+	}
+}