diff --git a/test/resources-local/c3p0.properties b/test/resources-local/c3p0.properties
index 6df259c6..a21bb2bb 100644
--- a/test/resources-local/c3p0.properties
+++ b/test/resources-local/c3p0.properties
@@ -4,7 +4,7 @@ c3p0.testConnectionOnCheckout=true
 #c3p0.minPoolSize=10
 #c3p0.maxPoolSize=40
 #c3p0.checkoutTimeout=2000
-c3p0.connectionIsValidTimeout=5
+#c3p0.connectionIsValidTimeout=5
 #c3p0.idleConnectionTestPeriod=30
 #c3p0.idleConnectionTestPeriod=1
 #c3p0.maxConnectionAge=10
@@ -31,6 +31,7 @@ c3p0.connectionIsValidTimeout=5
 #c3p0.contextClassLoaderSource=library
 #c3p0.privilegeSpawnedThreads=true
 #c3p0.connectionTesterClassName=com.mchange.v2.c3p0.test.AlwaysFailConnectionTester
+#c3p0.connectionTesterClassName=com.mchange.v2.c3p0.test.Percent20FailConnectionTester
 #c3p0.connectionTesterClassName=com.mchange.v2.c3p0.example.IsValidOnlyConnectionTester30
 #c3p0.taskRunnerFactoryClassName=com.mchange.v2.c3p0.test.LogCreationTaskRunnerFactory
 #c3p0.taskRunnerFactoryClassName=com.mchange.v2.c3p0.test.ThreadPerTaskRunnerFactory
diff --git a/test/src/com/mchange/v2/c3p0/test/AlwaysFailConnectionTester.java b/test/src/com/mchange/v2/c3p0/test/AlwaysFailConnectionTester.java
index 8e4ecdfa..4641e051 100644
--- a/test/src/com/mchange/v2/c3p0/test/AlwaysFailConnectionTester.java
+++ b/test/src/com/mchange/v2/c3p0/test/AlwaysFailConnectionTester.java
@@ -67,10 +67,7 @@ public int activeCheckConnection(Connection c, String preferredTestQuery)
 	return CONNECTION_IS_INVALID; 
     }
 
-    public boolean equals( Object o )
-    { return (o instanceof AlwaysFailConnectionTester); }
-
-    public int hashCode()
-    { return 1; }
+    public boolean equals( Object o ) { return this.getClass().equals( o.getClass() ); }
+    public int hashCode() { return this.getClass().getName().hashCode(); }
 }
 
diff --git a/test/src/com/mchange/v2/c3p0/test/Percent20FailConnectionTester.java b/test/src/com/mchange/v2/c3p0/test/Percent20FailConnectionTester.java
new file mode 100644
index 00000000..18d9867f
--- /dev/null
+++ b/test/src/com/mchange/v2/c3p0/test/Percent20FailConnectionTester.java
@@ -0,0 +1,46 @@
+package com.mchange.v2.c3p0.test;
+
+import java.sql.Connection;
+import com.mchange.v2.c3p0.QueryConnectionTester;
+import com.mchange.v2.log.MLevel;
+import com.mchange.v2.log.MLog;
+import com.mchange.v2.log.MLogger;
+
+public final class Percent20FailConnectionTester implements QueryConnectionTester
+{
+    final static MLogger logger = MLog.getLogger( Percent20FailConnectionTester.class );
+
+    {
+	//logger.log(MLevel.WARNING,  "Instantiated: " + this, new Exception("Instantiation Stack Trace.") );
+    }
+
+    private int roulette()
+    {
+	if (Math.random() < 0.20d)
+	    return CONNECTION_IS_INVALID;
+	else
+	    return CONNECTION_IS_OKAY;
+    }
+
+    public int activeCheckConnection(Connection c)
+    {
+	//logger.warning(this + ": activeCheckConnection(Connection c)");
+	return roulette(); 
+    }
+
+    public int statusOnException(Connection c, Throwable t)
+    { 
+	//logger.warning(this + ": statusOnException(Connection c, Throwable t)");
+	return roulette(); 
+    }
+
+    public int activeCheckConnection(Connection c, String preferredTestQuery)
+    { 
+	//logger.warning(this + ": activeCheckConnection(Connection c, String preferredTestQuery)");
+	return roulette(); 
+    }
+
+    public boolean equals( Object o ) { return this.getClass().equals( o.getClass() ); }
+    public int hashCode() { return this.getClass().getName().hashCode(); }
+}
+