diff --git a/src/java/org/apache/commons/math/special/Beta.java b/src/java/org/apache/commons/math/special/Beta.java
index 4239c252d..904e15663 100644
--- a/src/java/org/apache/commons/math/special/Beta.java
+++ b/src/java/org/apache/commons/math/special/Beta.java
@@ -33,7 +33,7 @@ public class Beta implements Serializable {
     private static final long serialVersionUID = -3833485397404128220L;
 
     /** Maximum allowed numerical error. */
-    private static final double DEFAULT_EPSILON = 10e-9;
+    private static final double DEFAULT_EPSILON = 10e-15;
 
     /**
      * Default constructor.  Prohibit instantiation.
diff --git a/src/java/org/apache/commons/math/special/Gamma.java b/src/java/org/apache/commons/math/special/Gamma.java
index 8c565cbff..ba2c4dbf3 100644
--- a/src/java/org/apache/commons/math/special/Gamma.java
+++ b/src/java/org/apache/commons/math/special/Gamma.java
@@ -34,7 +34,7 @@ public class Gamma implements Serializable {
     private static final long serialVersionUID = -6587513359895466954L;
 
     /** Maximum allowed numerical error. */
-    private static final double DEFAULT_EPSILON = 10e-9;
+    private static final double DEFAULT_EPSILON = 10e-15;
 
     /** Lanczos coefficients */
     private static double[] lanczos =
diff --git a/src/test/org/apache/commons/math/special/BetaTest.java b/src/test/org/apache/commons/math/special/BetaTest.java
index 5e916e246..01446afce 100644
--- a/src/test/org/apache/commons/math/special/BetaTest.java
+++ b/src/test/org/apache/commons/math/special/BetaTest.java
@@ -38,7 +38,7 @@ public class BetaTest extends TestCase {
     {
         try {
             double actual = Beta.regularizedBeta(x, a, b);
-            TestUtils.assertEquals(expected, actual, 10e-5);
+            TestUtils.assertEquals(expected, actual, 10e-15);
         } catch(MathException ex){
             fail(ex.getMessage());
         }
@@ -46,7 +46,7 @@ public class BetaTest extends TestCase {
 
     private void testLogBeta(double expected, double a, double b) {
         double actual = Beta.logBeta(a, b);
-        TestUtils.assertEquals(expected, actual, 10e-5);
+        TestUtils.assertEquals(expected, actual, 10e-15);
     }
 
     public void testRegularizedBetaNanPositivePositive() {
@@ -114,6 +114,6 @@ public class BetaTest extends TestCase {
     }
     
     public void testLogBetaPositivePositive() {
-        testLogBeta(-0.693147, 1.0, 2.0);
+        testLogBeta(-0.693147180559945, 1.0, 2.0);
     }
 }
\ No newline at end of file
diff --git a/src/test/org/apache/commons/math/special/GammaTest.java b/src/test/org/apache/commons/math/special/GammaTest.java
index e7524f1b6..e7d459616 100644
--- a/src/test/org/apache/commons/math/special/GammaTest.java
+++ b/src/test/org/apache/commons/math/special/GammaTest.java
@@ -37,8 +37,8 @@ public class GammaTest extends TestCase {
         try {
             double actualP = Gamma.regularizedGammaP(a, x);
             double actualQ = Gamma.regularizedGammaQ(a, x);
-            TestUtils.assertEquals(expected, actualP, 10e-5);
-            TestUtils.assertEquals(actualP, 1.0 - actualQ, 10e-5);
+            TestUtils.assertEquals(expected, actualP, 10e-15);
+            TestUtils.assertEquals(actualP, 1.0 - actualQ, 10e-15);
         } catch(MathException ex){
             fail(ex.getMessage());
         }
@@ -46,7 +46,7 @@ public class GammaTest extends TestCase {
 
     private void testLogGamma(double expected, double x) {
         double actual = Gamma.logGamma(x);
-        TestUtils.assertEquals(expected, actual, 10e-5);
+        TestUtils.assertEquals(expected, actual, 10e-15);
     }
 
     public void testRegularizedGammaNanPositive() {
@@ -74,7 +74,7 @@ public class GammaTest extends TestCase {
     }
     
     public void testRegularizedGammaPositivePositive() {
-        testRegularizedGamma(0.632121, 1.0, 1.0);
+        testRegularizedGamma(0.632120558828558, 1.0, 1.0);
     }
     
     public void testLogGammaNan() {
@@ -90,6 +90,6 @@ public class GammaTest extends TestCase {
     }
     
     public void testLogGammaPositive() {
-        testLogGamma(0.693147, 3.0);
+        testLogGamma(0.6931471805599457, 3.0);
     }
 }
diff --git a/xdocs/changes.xml b/xdocs/changes.xml
index f8f088c0e..441a7a262 100644
--- a/xdocs/changes.xml
+++ b/xdocs/changes.xml
@@ -78,6 +78,9 @@ Commons Math Release Notes</title>
       <action dev="brentworden" type="fix" issue="MATH-153" due-to="Remi Arntzen">
         Corrected nextInt and nextLong to handle wide value ranges.
       </action>
+      <action dev="psteitz" type="fix" issue="MATH-166" due-to="Lukas Theussl">
+        Increased default precision of Gamma and Beta functions.
+      </action>
     </release>
     <release version="1.1" date="2005-12-17"  
  description="This is a maintenance release containing bug fixes and enhancements.