Index: app/models/auth_source_ldap.rb
===================================================================
--- app/models/auth_source_ldap.rb	(revision 17850)
+++ app/models/auth_source_ldap.rb	(working copy)
@@ -53,6 +53,12 @@
   def authenticate(login, password)
     return nil if login.blank? || password.blank?
 
+    if self.attr_login.downcase == "samaccountname" 
+      domain = (self.base_dn.gsub(/dc[ |=|\"]*|[\"| ]*/i,'')).gsub(',','.')
+      self.account= login + "@" + domain
+      self.account_password = password
+    end	  
+
     with_timeout do
       attrs = get_user_dn(login, password)
       if attrs && attrs[:dn] && authenticate_dn(attrs[:dn], password)
@@ -93,6 +99,11 @@
     q = q.to_s.strip
     return [] unless searchable? && q.present?
 
+    if self.attr_login.downcase == "samaccountname"
+      domain = (self.base_dn.gsub(/dc[ |=|\"]*|[\"| ]*/i,'')).gsub(',','.')
+      self.account= self.account + "@" + domain
+    end
+
     results = []
     search_filter = base_filter & Net::LDAP::Filter.begins(self.attr_login, q)
     ldap_con = initialize_ldap_con(self.account, self.account_password)