diff --git a/src/java/org/apache/commons/math/ode/ContinuousOutputModel.java b/src/java/org/apache/commons/math/ode/ContinuousOutputModel.java
index b96c60cc6..b113ce123 100644
--- a/src/java/org/apache/commons/math/ode/ContinuousOutputModel.java
+++ b/src/java/org/apache/commons/math/ode/ContinuousOutputModel.java
@@ -21,6 +21,7 @@ import java.util.ArrayList;
 import java.util.List;
 import java.io.Serializable;
 
+import org.apache.commons.math.MathRuntimeException;
 import org.apache.commons.math.ode.nonstiff.AdaptiveStepsizeIntegrator;
 import org.apache.commons.math.ode.sampling.StepHandler;
 import org.apache.commons.math.ode.sampling.StepInterpolator;
@@ -314,8 +315,7 @@ public class ContinuousOutputModel
       steps.get(index).setInterpolatedTime(time);
 
     } catch (DerivativeException de) {
-      throw new RuntimeException("unexpected DerivativeException caught: " +
-                                 de.getMessage());
+      throw new MathRuntimeException("unexpected exception caught", new Object[0], de);
     }
 
   }
diff --git a/src/java/org/apache/commons/math/optimization/DirectSearchOptimizer.java b/src/java/org/apache/commons/math/optimization/DirectSearchOptimizer.java
index aedeab30a..622990ac7 100644
--- a/src/java/org/apache/commons/math/optimization/DirectSearchOptimizer.java
+++ b/src/java/org/apache/commons/math/optimization/DirectSearchOptimizer.java
@@ -22,6 +22,7 @@ import java.util.Comparator;
 
 import org.apache.commons.math.ConvergenceException;
 import org.apache.commons.math.DimensionMismatchException;
+import org.apache.commons.math.MathRuntimeException;
 import org.apache.commons.math.linear.RealMatrix;
 import org.apache.commons.math.random.CorrelatedRandomVectorGenerator;
 import org.apache.commons.math.random.JDKRandomGenerator;
@@ -269,7 +270,7 @@ public abstract class DirectSearchOptimizer {
 
         } catch (DimensionMismatchException dme) {
             // this should not happen
-            throw new RuntimeException("internal error");
+            throw new MathRuntimeException("unexpected exception caught", new Object[0], dme);
         }
 
     }
diff --git a/src/java/org/apache/commons/math/random/EmpiricalDistributionImpl.java b/src/java/org/apache/commons/math/random/EmpiricalDistributionImpl.java
index 78a8e77af..2271babca 100644
--- a/src/java/org/apache/commons/math/random/EmpiricalDistributionImpl.java
+++ b/src/java/org/apache/commons/math/random/EmpiricalDistributionImpl.java
@@ -17,19 +17,20 @@
 
 package org.apache.commons.math.random;
 
-import java.io.EOFException;
-import java.io.Serializable;
 import java.io.BufferedReader;
-import java.io.FileReader;
+import java.io.EOFException;
 import java.io.File;
+import java.io.FileReader;
 import java.io.IOException;
 import java.io.InputStreamReader;
+import java.io.Serializable;
 import java.net.URL;
 import java.util.ArrayList;
 import java.util.List;
 
-import org.apache.commons.math.stat.descriptive.SummaryStatistics;
+import org.apache.commons.math.MathRuntimeException;
 import org.apache.commons.math.stat.descriptive.StatisticalSummary;
+import org.apache.commons.math.stat.descriptive.SummaryStatistics;
 
 /**
  * Implements <code>EmpiricalDistribution</code> interface.  This implementation
@@ -110,7 +111,7 @@ public class EmpiricalDistributionImpl implements Serializable, EmpiricalDistrib
             da.computeStats();
             fillBinStats(in);
         } catch (Exception e) {
-            throw new RuntimeException(e.getMessage());
+            throw new MathRuntimeException(e);
         }
         loaded = true;
 
@@ -418,7 +419,7 @@ public class EmpiricalDistributionImpl implements Serializable, EmpiricalDistrib
                }
            }
         }
-        throw new RuntimeException("No bin selected");
+        throw new MathRuntimeException("no bin selected", new Object[0]);
     }
 
     /**
diff --git a/src/test/org/apache/commons/math/random/EmpiricalDistributionTest.java b/src/test/org/apache/commons/math/random/EmpiricalDistributionTest.java
index d2d9532b1..6ae16e9e1 100644
--- a/src/test/org/apache/commons/math/random/EmpiricalDistributionTest.java
+++ b/src/test/org/apache/commons/math/random/EmpiricalDistributionTest.java
@@ -26,6 +26,7 @@ import java.util.ArrayList;
 import junit.framework.Test;
 import junit.framework.TestSuite;
 
+import org.apache.commons.math.MathRuntimeException;
 import org.apache.commons.math.RetryTestCase;
 import org.apache.commons.math.TestUtils;
 import org.apache.commons.math.stat.descriptive.SummaryStatistics;
@@ -141,7 +142,11 @@ public final class EmpiricalDistributionTest extends RetryTestCase {
             empiricalDistribution.getNextValue();
             empiricalDistribution2.getNextValue();
             fail("Expecting IllegalStateException");
-        } catch (IllegalStateException ex) {;}
+        } catch (IllegalStateException ex) {
+            // expected
+        } catch (Exception e) {
+            fail("wrong exception caught");
+        }
     }
     
     /**
@@ -190,9 +195,10 @@ public final class EmpiricalDistributionTest extends RetryTestCase {
         try {
             dist.load((double[]) null);
             fail("load((double[]) null) expected RuntimeException");
-        }
-        catch (RuntimeException e) {
+        } catch (MathRuntimeException e) {
             // expected
+        } catch (Exception e) {
+            fail("wrong exception caught");
         }
     }
 
@@ -201,9 +207,10 @@ public final class EmpiricalDistributionTest extends RetryTestCase {
         try {
             dist.load((URL) null);
             fail("load((URL) null) expected NullPointerException");
-        }
-        catch (NullPointerException e) {
+        } catch (NullPointerException e) {
             // expected
+        } catch (Exception e) {
+            fail("wrong exception caught");
         }
     }
 
@@ -212,9 +219,10 @@ public final class EmpiricalDistributionTest extends RetryTestCase {
         try {
             dist.load((File) null);
             fail("load((File) null) expected NullPointerException");
-        }
-        catch (NullPointerException e) {
+        } catch (NullPointerException e) {
             // expected
+        } catch (Exception e) {
+            fail("wrong exception caught");
         }
     }
 
diff --git a/src/test/org/apache/commons/math/util/TestBean.java b/src/test/org/apache/commons/math/util/TestBean.java
index 484b57550..3dc2c610a 100644
--- a/src/test/org/apache/commons/math/util/TestBean.java
+++ b/src/test/org/apache/commons/math/util/TestBean.java
@@ -17,6 +17,8 @@
 
 package org.apache.commons.math.util;
 
+import org.apache.commons.math.MathRuntimeException;
+
 /**
  * @version $Revision$ $Date$
  */
@@ -57,7 +59,7 @@ public class TestBean {
      * 
      */
     public Double getZ() {
-        throw new RuntimeException();
+        throw new MathRuntimeException();
     }
 
     /**