diff --git a/test/src/com/mchange/v2/c3p0/test/Percent20FailConnectionTester.java b/test/src/com/mchange/v2/c3p0/test/Percent20FailConnectionTester.java
index 18d9867f..dfd5d72b 100644
--- a/test/src/com/mchange/v2/c3p0/test/Percent20FailConnectionTester.java
+++ b/test/src/com/mchange/v2/c3p0/test/Percent20FailConnectionTester.java
@@ -6,41 +6,9 @@
 import com.mchange.v2.log.MLog;
 import com.mchange.v2.log.MLogger;
 
-public final class Percent20FailConnectionTester implements QueryConnectionTester
+public final class Percent20FailConnectionTester extends PercentXXFailConnectionTester
 {
-    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(); }
+    public Percent20FailConnectionTester()
+    { super(20); }
 }
 
diff --git a/test/src/com/mchange/v2/c3p0/test/Percent80FailConnectionTester.java b/test/src/com/mchange/v2/c3p0/test/Percent80FailConnectionTester.java
index 2e973946..aa8bb933 100644
--- a/test/src/com/mchange/v2/c3p0/test/Percent80FailConnectionTester.java
+++ b/test/src/com/mchange/v2/c3p0/test/Percent80FailConnectionTester.java
@@ -6,41 +6,9 @@
 import com.mchange.v2.log.MLog;
 import com.mchange.v2.log.MLogger;
 
-public final class Percent80FailConnectionTester implements QueryConnectionTester
+public final class Percent80FailConnectionTester extends PercentXXFailConnectionTester
 {
-    final static MLogger logger = MLog.getLogger( Percent80FailConnectionTester.class );
-
-    {
-	//logger.log(MLevel.WARNING,  "Instantiated: " + this, new Exception("Instantiation Stack Trace.") );
-    }
-
-    private int roulette()
-    {
-	if (Math.random() < 0.80d)
-	    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(); }
+    public Percent80FailConnectionTester()
+    { super(80); }
 }
 
diff --git a/test/src/com/mchange/v2/c3p0/test/PercentXXFailConnectionTester.java b/test/src/com/mchange/v2/c3p0/test/PercentXXFailConnectionTester.java
new file mode 100644
index 00000000..3963844f
--- /dev/null
+++ b/test/src/com/mchange/v2/c3p0/test/PercentXXFailConnectionTester.java
@@ -0,0 +1,52 @@
+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 abstract class PercentXXFailConnectionTester implements QueryConnectionTester
+{
+    //final static MLogger logger = MLog.getLogger( PercentXXFailConnectionTester.class );
+
+    double threshold;
+
+    protected PercentXXFailConnectionTester(int pct)
+    {
+        if (pct < 0 || pct > 100)
+            throw new IllegalArgumentException("Percentage must be between 0 and 100, found " + pct + ".");
+        this.threshold = pct / 100d;
+	//logger.log(MLevel.WARNING,  "Instantiated: " + this, new Exception("Instantiation Stack Trace.") );
+    }
+
+    private int roulette()
+    {
+	if (Math.random() < threshold)
+	    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(); }
+}
+