Better fallback for defauls on autoupgrade opration?

[carlosacp]

I Tried

class A
include DataMapper::Resource
property :id, Serial
property :no_recipes_with, Object, default: ""
end

and when autoupgrade :

rake db:autoupgrade
rake aborted!
BLOB/TEXT column 'no_recipes_with' can't have a default value

(mysql)

But if I remove the default value, upgrade the database, and put the default value again back, it works.
Wouldn't be a better fall back if it uses de default value in model objects in this cases?
Or I'm not supposed to use default value if upgrade fails?