diff --git a/maven-settings-builder/pom.xml b/maven-settings-builder/pom.xml
index ff4fcd4576..7ca6081eb9 100644
--- a/maven-settings-builder/pom.xml
+++ b/maven-settings-builder/pom.xml
@@ -39,6 +39,12 @@ under the License.
     <tag>HEAD</tag>
   </scm>
 
+  <contributors>
+    <contributor>
+      <name>Thomas Meyer</name>
+    </contributor>
+  </contributors>
+
   <dependencies>
     <dependency>
       <groupId>org.apache.maven</groupId>
diff --git a/maven-settings-builder/src/main/java/org/apache/maven/settings/validation/DefaultSettingsValidator.java b/maven-settings-builder/src/main/java/org/apache/maven/settings/validation/DefaultSettingsValidator.java
index aa4d30316f..b32471113f 100644
--- a/maven-settings-builder/src/main/java/org/apache/maven/settings/validation/DefaultSettingsValidator.java
+++ b/maven-settings-builder/src/main/java/org/apache/maven/settings/validation/DefaultSettingsValidator.java
@@ -26,6 +26,7 @@
 import org.apache.maven.settings.Mirror;
 import org.apache.maven.settings.Profile;
 import org.apache.maven.settings.Repository;
+import org.apache.maven.settings.Proxy;
 import org.apache.maven.settings.Server;
 import org.apache.maven.settings.Settings;
 import org.apache.maven.settings.building.SettingsProblem.Severity;
@@ -141,6 +142,23 @@ else if ( !pluginGroup.matches( ID_REGEX ) )
                     + "pluginRepositories.pluginRepository" );
             }
         }
+
+        List<Proxy> proxies = settings.getProxies();
+
+        if ( proxies != null )
+        {
+            Set<String> proxyIds = new HashSet<String>();
+            
+            for ( Proxy proxy : proxies )
+            {
+                if ( !proxyIds.add( proxy.getId() ) )
+                {
+                    addViolation( problems, Severity.WARNING, "proxies.proxy.id", null,
+                                  "must be unique but found duplicate proxy with id " + proxy.getId() );
+                }
+                validateStringNotEmpty( problems, "proxies.proxy.host", proxy.getHost(), proxy.getId() );
+            }
+        }
     }
 
     private void validateRepositories( SettingsProblemCollector problems, List<Repository> repositories, String prefix )
@@ -189,7 +207,7 @@ private void validateRepositories( SettingsProblemCollector problems, List<Repos
      * <li><code>string.length > 0</code>
      * </ul>
      */
-    private boolean validateStringNotEmpty( SettingsProblemCollector problems, String fieldName, String string,
+    private static boolean validateStringNotEmpty( SettingsProblemCollector problems, String fieldName, String string,
                                             String sourceHint )
     {
         if ( !validateNotNull( problems, fieldName, string, sourceHint ) )
@@ -214,7 +232,7 @@ private boolean validateStringNotEmpty( SettingsProblemCollector problems, Strin
      * <li><code>string != null</code>
      * </ul>
      */
-    private boolean validateNotNull( SettingsProblemCollector problems, String fieldName, Object object,
+    private static boolean validateNotNull( SettingsProblemCollector problems, String fieldName, Object object,
                                      String sourceHint )
     {
         if ( object != null )
@@ -227,7 +245,7 @@ private boolean validateNotNull( SettingsProblemCollector problems, String field
         return false;
     }
 
-    private boolean validateBannedCharacters( SettingsProblemCollector problems, String fieldName, Severity severity,
+    private static boolean validateBannedCharacters( SettingsProblemCollector problems, String fieldName, Severity severity,
                                               String string, String sourceHint, String banned )
     {
         if ( string != null )
@@ -247,7 +265,7 @@ private boolean validateBannedCharacters( SettingsProblemCollector problems, Str
         return true;
     }
 
-    private void addViolation( SettingsProblemCollector problems, Severity severity, String fieldName,
+    private static void addViolation( SettingsProblemCollector problems, Severity severity, String fieldName,
                                String sourceHint, String message )
     {
         StringBuilder buffer = new StringBuilder( 256 );
diff --git a/maven-settings-builder/src/test/java/org/apache/maven/settings/validation/DefaultSettingsValidatorTest.java b/maven-settings-builder/src/test/java/org/apache/maven/settings/validation/DefaultSettingsValidatorTest.java
index fe6988b8f2..8c7f21d82e 100644
--- a/maven-settings-builder/src/test/java/org/apache/maven/settings/validation/DefaultSettingsValidatorTest.java
+++ b/maven-settings-builder/src/test/java/org/apache/maven/settings/validation/DefaultSettingsValidatorTest.java
@@ -26,6 +26,7 @@
 
 import org.apache.maven.settings.Mirror;
 import org.apache.maven.settings.Profile;
+import org.apache.maven.settings.Proxy;
 import org.apache.maven.settings.Repository;
 import org.apache.maven.settings.Server;
 import org.apache.maven.settings.Settings;
@@ -195,6 +196,38 @@ public void testValidateUniqueRepositoryId()
             + " but found duplicate repository with id test" );
     }
 
+    public void testValidateUniqueProxyId()
+        throws Exception
+    {
+        Settings settings = new Settings();
+        Proxy proxy = new Proxy();
+        String id = null;
+        proxy.setId( id );
+        proxy.setHost("www.example.com");
+        settings.addProxy( proxy );
+        settings.addProxy( proxy );
+
+        SimpleProblemCollector problems = new SimpleProblemCollector();
+        validator.validate( settings, problems );
+        assertEquals( 1, problems.messages.size() );
+        assertContains( problems.messages.get( 0 ), "'proxies.proxy.id' must be unique"
+            + " but found duplicate proxy with id " + id );
+
+    }
+
+    public void testValidateProxy()
+        throws Exception
+    {
+        Settings settings = new Settings();
+        Proxy proxy1 = new Proxy();
+        settings.addProxy( proxy1 );
+
+        SimpleProblemCollector problems = new SimpleProblemCollector();
+        validator.validate( settings, problems );
+        assertEquals( 1, problems.messages.size() );
+        assertContains( problems.messages.get( 0 ), "'proxies.proxy.host' for default is missing" );
+    }
+
     private static class SimpleProblemCollector
         implements SettingsProblemCollector
     {