title: south migration error app "is not available in this migration"
body: <p>This problem is basically the same as the previous question
  <a href="https://stackoverflow.com/questions/880989/error-when-trying-to-migrate-django-application-with-south">here</a>.</p>
  
  <p>However, the answer there does not work for me. I've installed the trunk version of south, manually entered the import line in the migration file in question, and done a full 'startmigration' in a separate directory and examined the 0001_initial.py file.</p>
  
  <p>I have a Django project with several applications in it, one of them (named 'core') being referred to by the others. The south migration is trying to create a new table, with a column that has a foreign key to a model in core.</p>
  
  <p>I'm currently importing core in the migration in question (0006), and I even added it to migration 0001, although it doesn't seem like that should matter.</p>
  
  <p>Before I do something drastic, like removing that field, running the migration, and adding the field manually, is there a known manual workaround for fixing this south issue?</p>