problem with tests and custom mysql fulltext indexes

I'm using Rails 2.0.2 / MySQL 5.0.45

I think it's a kind of bug/problem for tests and mysql fulltext indexes, which doesn't have a common workaround.

So, it goes like this:

I have this in my migration:

execute "CREATE FULLTEXT INDEX fulltext_summary ON indexed_stories (summary)"

where "summary" is mysql text field.

The problem that I see is that when running "rake db:test:prepare" it always loads "schema.rb". However in it, instead of the above custom execute we have this line:

add_index "indexed_stories", ["summary"], :name => "fulltext_summary"

which tries to create a normal index and dies with:

Mysql::Error: BLOB/TEXT column 'summary' used in key specification without a key length: CREATE INDEX `fulltext_title_summary` ON `indexed_stories` (`title`, `summary`)

Is there a work-around for such situations where we're using custom sql in migrations?