Fixed unit tests and fixture loading for postgres. The foreign keys were playing havoc with the tests when only some fixtures were loaded.

test/unit/diary_comment_test.rb

@@ -1,9 +1,9 @@
 require File.dirname(__FILE__) + '/../test_helper'
 
 class DiaryCommentTest < Test::Unit::TestCase
+  api_fixtures
   fixtures :diary_comments
   
-  
   def test_diary_comment_count
     assert_equal 1, DiaryComment.count
   end