diff --git a/pom.xml b/pom.xml
index d450441f..1e543eff 100644
--- a/pom.xml
+++ b/pom.xml
@@ -63,7 +63,7 @@
         <dependency>
           <groupId>org.jenkins-ci.plugins</groupId>
           <artifactId>github-api</artifactId>
-          <version>1.34</version>
+          <version>1.28</version>
         </dependency>
 
 		<dependency>
diff --git a/src/main/java/org/jenkinsci/plugins/GithubSecurityRealm.java b/src/main/java/org/jenkinsci/plugins/GithubSecurityRealm.java
index cb2aa396..e4b4ada7 100644
--- a/src/main/java/org/jenkinsci/plugins/GithubSecurityRealm.java
+++ b/src/main/java/org/jenkinsci/plugins/GithubSecurityRealm.java
@@ -26,27 +26,18 @@ of this software and associated documentation files (the "Software"), to deal
  */
 package org.jenkinsci.plugins;
 
+import com.thoughtworks.xstream.converters.ConversionException;
+import com.thoughtworks.xstream.converters.Converter;
+import com.thoughtworks.xstream.converters.MarshallingContext;
+import com.thoughtworks.xstream.converters.UnmarshallingContext;
+import com.thoughtworks.xstream.io.HierarchicalStreamReader;
+import com.thoughtworks.xstream.io.HierarchicalStreamWriter;
 import hudson.Extension;
 import hudson.Util;
 import hudson.model.Descriptor;
-import hudson.model.Fingerprint.RangeSet;
 import hudson.model.User;
 import hudson.security.GroupDetails;
-import hudson.security.Permission;
-import hudson.security.HudsonPrivateSecurityRealm.Details;
 import hudson.security.SecurityRealm;
-
-import java.io.IOException;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Set;
-import java.util.SortedMap;
-import java.util.TreeMap;
-import java.util.Map.Entry;
-import java.util.logging.Logger;
-
 import hudson.tasks.Mailer;
 import jenkins.model.Jenkins;
 import org.acegisecurity.Authentication;
@@ -54,12 +45,9 @@ of this software and associated documentation files (the "Software"), to deal
 import org.acegisecurity.AuthenticationManager;
 import org.acegisecurity.BadCredentialsException;
 import org.acegisecurity.context.SecurityContextHolder;
-import org.acegisecurity.providers.UsernamePasswordAuthenticationToken;
-import org.acegisecurity.providers.anonymous.AnonymousAuthenticationToken;
 import org.acegisecurity.userdetails.UserDetails;
 import org.acegisecurity.userdetails.UserDetailsService;
 import org.acegisecurity.userdetails.UsernameNotFoundException;
-import org.apache.bcel.generic.ATHROW;
 import org.apache.http.HttpEntity;
 import org.apache.http.client.methods.HttpPost;
 import org.apache.http.impl.client.DefaultHttpClient;
@@ -67,7 +55,6 @@ of this software and associated documentation files (the "Software"), to deal
 import org.jfree.util.Log;
 import org.kohsuke.github.GHOrganization;
 import org.kohsuke.github.GHUser;
-import org.kohsuke.github.GitHub;
 import org.kohsuke.stapler.DataBoundConstructor;
 import org.kohsuke.stapler.Header;
 import org.kohsuke.stapler.HttpRedirect;
@@ -77,12 +64,10 @@ of this software and associated documentation files (the "Software"), to deal
 import org.springframework.dao.DataAccessException;
 import org.springframework.dao.DataRetrievalFailureException;
 
-import com.thoughtworks.xstream.converters.ConversionException;
-import com.thoughtworks.xstream.converters.Converter;
-import com.thoughtworks.xstream.converters.MarshallingContext;
-import com.thoughtworks.xstream.converters.UnmarshallingContext;
-import com.thoughtworks.xstream.io.HierarchicalStreamReader;
-import com.thoughtworks.xstream.io.HierarchicalStreamWriter;
+import java.io.IOException;
+import java.util.HashSet;
+import java.util.Set;
+import java.util.logging.Logger;
 
 /**
  * 
@@ -268,7 +253,7 @@ public HttpResponse doCommenceLogin(StaplerRequest request, @Header("Referer") f
             suffix = "&scope="+Util.join(scopes,",");
         }
 
-		return new HttpRedirect(githubUri + "/login/oauth/authorize?client_id="
+		return new HttpRedirect(extractAuthenticationUrl(githubUri) + "/login/oauth/authorize?client_id="
 				+ clientID + suffix);
 	}
 
@@ -286,9 +271,7 @@ public HttpResponse doFinishLogin(StaplerRequest request)
 			return HttpResponses.redirectToContextRoot();
 		}
 
-		Log.info("test");
-
-		HttpPost httpost = new HttpPost(githubUri
+		HttpPost httpost = new HttpPost(extractAuthenticationUrl(githubUri)
 				+ "/login/oauth/access_token?" + "client_id=" + clientID + "&"
 				+ "client_secret=" + clientSecret + "&" + "code=" + code);
 
@@ -309,8 +292,10 @@ public HttpResponse doFinishLogin(StaplerRequest request)
 		
 		if (accessToken != null && accessToken.trim().length() > 0) {
 
+			String githubServer = githubUri.replaceFirst("http.*\\/\\/", "");
+			
 			// only set the access token if it exists.
-            GithubAuthenticationToken auth = new GithubAuthenticationToken(accessToken,githubUri);
+            GithubAuthenticationToken auth = new GithubAuthenticationToken(accessToken,githubServer);
             SecurityContextHolder.getContext().setAuthentication(auth);
 
             GHUser self = auth.getGitHub().getMyself();
@@ -327,6 +312,16 @@ public HttpResponse doFinishLogin(StaplerRequest request)
 		return HttpResponses.redirectToContextRoot();   // referer should be always there, but be defensive
 	}
 
+    protected String extractAuthenticationUrl(String apiUrl) {
+        if (!apiUrl.equalsIgnoreCase(DEFAULT_URI)) {
+            int index = apiUrl.lastIndexOf("/api");
+            if (index != -1) {
+                return apiUrl.substring(0, index);
+            }
+        }
+        return apiUrl;
+    }
+
 	private String extractToken(String content) {
 
 		String parts[] = content.split("&");
diff --git a/src/test/java/org/jenkinsci/plugins/GithubSecurityRealmTest.java b/src/test/java/org/jenkinsci/plugins/GithubSecurityRealmTest.java
new file mode 100644
index 00000000..5f591e30
--- /dev/null
+++ b/src/test/java/org/jenkinsci/plugins/GithubSecurityRealmTest.java
@@ -0,0 +1,27 @@
+package org.jenkinsci.plugins;
+
+import junit.framework.TestCase;
+
+/**
+ * @author Johno Crawford (johno@hellface.com)
+ */
+public class GithubSecurityRealmTest extends TestCase {
+
+    private GithubSecurityRealm realm;
+
+    @Override
+    public void setUp() throws Exception {
+        super.setUp();
+        realm = new GithubSecurityRealm(null, null, null);
+    }
+
+    public void testGitHubServerUrl() throws Exception {
+        String authenticationUrl = realm.extractAuthenticationUrl("https://github.com");
+        assertEquals("https://github.com", authenticationUrl);
+    }
+
+    public void testEnterpriseServerUrl() throws Exception {
+        String authenticationUrl = realm.extractAuthenticationUrl("http://ghe.acme.com/api/v3/");
+        assertEquals("http://ghe.acme.com", authenticationUrl);
+    }
+}