diff --git a/linkcheck/project.properties b/linkcheck/project.properties
index 5bd71751..b240855c 100644
--- a/linkcheck/project.properties
+++ b/linkcheck/project.properties
@@ -24,6 +24,8 @@ maven.junit.sysproperties = \
   maven.proxy.port \
   maven.proxy.username \
   maven.proxy.password \
+  maven.proxy.ntlm.host \
+  maven.proxy.ntlm.domain \
   maven.mode.online
 
 maven.jar.override = on
diff --git a/linkcheck/src/main/org/apache/maven/plugin/linkcheck/LinkCheck.java b/linkcheck/src/main/org/apache/maven/plugin/linkcheck/LinkCheck.java
index 12699b04..34ff33c4 100644
--- a/linkcheck/src/main/org/apache/maven/plugin/linkcheck/LinkCheck.java
+++ b/linkcheck/src/main/org/apache/maven/plugin/linkcheck/LinkCheck.java
@@ -58,6 +58,10 @@ public final class LinkCheck
 
     private static final long MEG = 1024 * 1024;
 
+    private static final String MAVEN_PROXY_NTLM_HOST = "maven.proxy.ntlm.host";
+
+    private static final String MAVEN_PROXY_NTLM_DOMAIN = "maven.proxy.ntlm.domain";
+
     private File basedir;
 
     private String cache;
@@ -169,7 +173,9 @@ public final class LinkCheck
                 if ( ctx.getOnline().booleanValue() )
                 {
                     lvm.addLinkValidator( new OnlineHTTPLinkValidator( ctx.getProxyHost(), ctx.getProxyPort(), ctx
-                        .getProxyUserName(), ctx.getProxyPassword() ) );
+                        .getProxyUserName(), ctx.getProxyPassword(), (String) ctx.getVariable( MAVEN_PROXY_NTLM_HOST ),
+                                                                       (String) ctx
+                                                                           .getVariable( MAVEN_PROXY_NTLM_DOMAIN ) ) );
                 }
                 else
                 {
diff --git a/linkcheck/src/main/org/apache/maven/plugin/linkcheck/validation/OnlineHTTPLinkValidator.java b/linkcheck/src/main/org/apache/maven/plugin/linkcheck/validation/OnlineHTTPLinkValidator.java
index abbb7362..bbcb81fd 100644
--- a/linkcheck/src/main/org/apache/maven/plugin/linkcheck/validation/OnlineHTTPLinkValidator.java
+++ b/linkcheck/src/main/org/apache/maven/plugin/linkcheck/validation/OnlineHTTPLinkValidator.java
@@ -6,6 +6,7 @@ package org.apache.maven.plugin.linkcheck.validation;
 import java.io.IOException;
 import java.net.URL;
 
+import org.apache.commons.httpclient.Credentials;
 import org.apache.commons.httpclient.Header;
 import org.apache.commons.httpclient.HostConfiguration;
 import org.apache.commons.httpclient.HttpClient;
@@ -13,6 +14,7 @@ import org.apache.commons.httpclient.HttpException;
 import org.apache.commons.httpclient.HttpMethod;
 import org.apache.commons.httpclient.HttpState;
 import org.apache.commons.httpclient.HttpStatus;
+import org.apache.commons.httpclient.NTCredentials;
 import org.apache.commons.httpclient.StatusLine;
 import org.apache.commons.httpclient.UsernamePasswordCredentials;
 import org.apache.commons.httpclient.methods.HeadMethod;
@@ -41,9 +43,14 @@ public final class OnlineHTTPLinkValidator
 
     private String proxyPass;
 
+    private String proxyNtlmHost;
+
+    private String proxyNtlmDomain;
+
     private transient HttpClient cl;
 
-    public OnlineHTTPLinkValidator( String proxyHost, String proxyPort, String proxyUser, String proxyPass )
+    public OnlineHTTPLinkValidator( String proxyHost, String proxyPort, String proxyUser, String proxyPass,
+                                   String proxyNtlmHost, String proxyNtlmDomain )
     {
         if ( proxyHost == null || proxyHost.trim().equals( "" ) )
         {
@@ -67,6 +74,11 @@ public final class OnlineHTTPLinkValidator
             }
             this.proxyUser = proxyUser;
             this.proxyPass = proxyPass;
+            if ( proxyNtlmHost != null && proxyNtlmHost.trim().equals( "" ) )
+            {
+                this.proxyNtlmHost = proxyNtlmHost;
+                this.proxyNtlmDomain = proxyNtlmDomain;
+            }
         }
         initHttpClient();
     }
@@ -159,8 +171,17 @@ public final class OnlineHTTPLinkValidator
             {
                 if ( LOG.isDebugEnabled() )
                     LOG.debug( "Proxy User:" + proxyUser );
-                state
-                    .setProxyCredentials( null, null, new UsernamePasswordCredentials( this.proxyUser, this.proxyPass ) );
+                Credentials credentials;
+                if ( this.proxyNtlmHost != null )
+                {
+                    credentials = new NTCredentials( this.proxyUser, this.proxyPass, this.proxyNtlmHost,
+                                                     this.proxyNtlmDomain );
+                }
+                else
+                {
+                    credentials = new UsernamePasswordCredentials( this.proxyUser, this.proxyPass );
+                }
+                state.setProxyCredentials( null, null, credentials );
             }
 
         }
diff --git a/linkcheck/src/test/org/apache/maven/plugin/linkcheck/validation/HTTPLinkValidatorTest.java b/linkcheck/src/test/org/apache/maven/plugin/linkcheck/validation/HTTPLinkValidatorTest.java
index 8e21af08..8a1cbb81 100644
--- a/linkcheck/src/test/org/apache/maven/plugin/linkcheck/validation/HTTPLinkValidatorTest.java
+++ b/linkcheck/src/test/org/apache/maven/plugin/linkcheck/validation/HTTPLinkValidatorTest.java
@@ -41,7 +41,8 @@ public class HTTPLinkValidatorTest
         {
             hlv = new OnlineHTTPLinkValidator( System.getProperty( "maven.proxy.host" ), System
                 .getProperty( "maven.proxy.port" ), System.getProperty( "maven.proxy.username" ), System
-                .getProperty( "maven.proxy.password" ) );
+                .getProperty( "maven.proxy.password" ), System.getProperty( "maven.proxy.ntlm.host" ), System
+                .getProperty( "maven.proxy.ntlm.domain" ) );
 
             assertEquals( LinkValidationResult.VALID, checkLink( "http://www.apache.org" ).getStatus() );
             assertEquals( LinkValidationResult.ERROR, checkLink( "http://www.example.com>);" ).getStatus() );
diff --git a/linkcheck/xdocs/changes.xml b/linkcheck/xdocs/changes.xml
index 428ce483..6db8124b 100644
--- a/linkcheck/xdocs/changes.xml
+++ b/linkcheck/xdocs/changes.xml
@@ -34,6 +34,7 @@
       <action dev="aheritier" type="fix" issue="MPLINKCHECK-22">Sites requiring authentication are reported as NOT FOUND.</action>
       <action dev="aheritier" type="fix" issue="MPLINKCHECK-21">java.lang.NumberFormatException if proxy port is setted to ""</action>
       <action dev="aheritier" type="fix" issue="MPLINKCHECK-20" due-to="Ignacio G. Mac Dowell">StackOverflowError processing apidocs/index-all.html.</action>
+      <action dev="aheritier" type="add" issue="MPLINKCHECK-19">Support NTLM proxies.</action>
       <action dev="aheritier" type="update" issue="MPLINKCHECK-10">"Moved Permanently" sites are reported as a warning and not as an error.</action>
       <action dev="aheritier" type="add">If maven is in offline mode the report doesn't test external urls. A warning is displayed in the report.</action>
       <action dev="brett" type="update">Make compatible with Maven 1.1</action>