just a guess, but have you given any of your models a "type" field in the database? rails by default will think that your model is using STI if you have a "type" field.
aha... you should have caught that in your unit tests 
just a guess, but have you given any of your models a "type" field in the database? rails by default will think that your model is using STI if you have a "type" field.
aha... you should have caught that in your unit tests