Index: src/main/java/org/apache/tomcat/jdbc/pool/ConnectionPool.java
===================================================================
--- src/main/java/org/apache/tomcat/jdbc/pool/ConnectionPool.java	(revision 1180904)
+++ src/main/java/org/apache/tomcat/jdbc/pool/ConnectionPool.java	(working copy)
@@ -307,7 +307,7 @@
             getProxyConstructor(con.getXAConnection() != null);
             //create the proxy
             //TODO possible optimization, keep track if this connection was returned properly, and don't generate a new facade
-            Connection connection = (Connection)proxyClassConstructor.newInstance(new Object[] { handler });
+            Connection connection = (Connection)proxyClassConstructor.newInstance(new Object[] { new ProxyCutOffConnection(handler) });
             //return the connection
             return connection;
         }catch (Exception x) {
Index: src/main/java/org/apache/tomcat/jdbc/pool/ProxyCutOffConnection.java
===================================================================
--- src/main/java/org/apache/tomcat/jdbc/pool/ProxyCutOffConnection.java	(revision 0)
+++ src/main/java/org/apache/tomcat/jdbc/pool/ProxyCutOffConnection.java	(working copy)
@@ -0,0 +1,66 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF 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
+ *
+ *      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.apache.tomcat.jdbc.pool;
+
+import java.lang.reflect.Method;
+import java.sql.SQLException;
+
+/**
+ * A ProxyCutOffConnection object is the top most interceptor that wraps an object of type
+ * {@link PooledConnection}. The ProxyCutOffConnection intercepts two methods:
+ * <ul>
+ *   <li>{@link java.sql.Connection#close()} - returns the connection to the pool then breaks the link between cutoff and the next interceptor. May be called multiple times.</li>
+ *   <li>{@link java.lang.Object#toString()} - returns a custom string for this object</li>
+ * </ul>
+ * By default method comparisons is done on a String reference level, unless the {@link PoolConfiguration#setUseEquals(boolean)} has been called
+ * with a <code>true</code> argument.
+ * @author Filip Hanik
+ */
+public class ProxyCutOffConnection extends JdbcInterceptor {
+    protected ProxyCutOffConnection(JdbcInterceptor interceptor) throws SQLException {
+        setUseEquals(interceptor.isUseEquals());
+        setNext(interceptor);
+    }
+
+    @Override
+    public void reset(ConnectionPool parent, PooledConnection con) {
+    }
+
+    @Override
+    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
+        if (compare(ISCLOSED_VAL, method) && getNext() == null) {
+            return Boolean.TRUE;
+        }
+
+        try {
+            return super.invoke(proxy, method, args);
+        } catch (NullPointerException e) {
+            if (getNext() == null) {
+                if (compare(TOSTRING_VAL, method)) {
+                    return "ProxyConnection[null]";
+                }
+                throw new SQLException("Connection has already been closed.");
+            }
+
+            throw e;
+        } finally {
+            if (compare(CLOSE_VAL, method)) {
+                setNext(null);
+            }
+        }
+    }
+}
Index: src/test/java/org/apache/tomcat/jdbc/test/MultipleCloseTest.java
===================================================================
--- src/test/java/org/apache/tomcat/jdbc/test/MultipleCloseTest.java	(revision 0)
+++ src/test/java/org/apache/tomcat/jdbc/test/MultipleCloseTest.java	(working copy)
@@ -0,0 +1,66 @@
+/*
+ *  Licensed to the Apache Software Foundation (ASF) under one or more
+ *  contributor license agreements.  See the NOTICE file distributed with
+ *  this work for additional information regarding copyright ownership.
+ *  The ASF 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
+ *
+ *      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.apache.tomcat.jdbc.test;
+
+import java.sql.Connection;
+import org.apache.tomcat.jdbc.test.driver.Driver;
+
+public class MultipleCloseTest extends DefaultTestCase {
+
+    public MultipleCloseTest(String name) {
+        super(name);
+    }
+    
+    @Override
+    public org.apache.tomcat.jdbc.pool.DataSource createDefaultDataSource() {
+        org.apache.tomcat.jdbc.pool.DataSource ds = super.createDefaultDataSource();
+        ds.getPoolProperties().setDriverClassName(Driver.class.getName());
+        ds.getPoolProperties().setUrl(Driver.url);
+        ds.getPoolProperties().setInitialSize(0);
+        ds.getPoolProperties().setMaxIdle(1);
+        ds.getPoolProperties().setMinIdle(1);
+        ds.getPoolProperties().setMaxActive(1);
+        return ds;
+    }
+
+    @Override
+    protected void tearDown() throws Exception {
+        Driver.reset();
+        super.tearDown();
+    }
+
+    public void testClosedConnectionsNotReused() throws Exception {
+        this.init();
+        
+        Connection con1 = datasource.getConnection();
+
+        // A new connection is open
+        assertFalse(con1.isClosed());
+
+        con1.close();
+
+        // Confirm that a closed connection is closed
+        assertTrue(con1.isClosed());
+
+        // Open a new connection (This will re-use the previous pooled connection)
+        datasource.getConnection();
+        
+        // A connection, once closed, should stay closed
+        assertTrue(con1.isClosed());
+    }    
+}