diff --git a/activerecord/CHANGELOG b/activerecord/CHANGELOG
index bb1c705913d..80218b90701 100644
--- a/activerecord/CHANGELOG
+++ b/activerecord/CHANGELOG
@@ -1,5 +1,8 @@
 *CVS*
 
+* Fixed has_and_belongs_to_many guessing of foreign key so that keys are generated correctly for models like SomeVerySpecialClient 
+  [Florian Weber]
+
 * Added counter_sql option for has_many associations [bitsweat]. Documentation:
 
     <tt>:counter_sql</tt> - specify a complete SQL statement to fetch the size of the association. If +:finder_sql+ is
diff --git a/activerecord/lib/active_record/associations/has_and_belongs_to_many_association.rb b/activerecord/lib/active_record/associations/has_and_belongs_to_many_association.rb
index fd36352deb2..8dec71403cd 100644
--- a/activerecord/lib/active_record/associations/has_and_belongs_to_many_association.rb
+++ b/activerecord/lib/active_record/associations/has_and_belongs_to_many_association.rb
@@ -4,7 +4,7 @@ module ActiveRecord
       def initialize(owner, association_name, association_class_name, association_class_primary_key_name, join_table, options)
         super(owner, association_name, association_class_name, association_class_primary_key_name, options)
             
-        @association_foreign_key = options[:association_foreign_key] || Inflector.underscore(Inflector.demodulize(association_class_name.downcase)) + "_id"
+        @association_foreign_key = options[:association_foreign_key] || Inflector.underscore(Inflector.demodulize(association_class_name)) + "_id"
         association_table_name = options[:table_name] || @association_class.table_name(association_class_name)
         @join_table = join_table
         @order = options[:order] || "t.#{@owner.class.primary_key}"