Currently, we can't make a call to ActiveRecord::Base#find,
#find_by_*, #find_all_by_*, #exists?, #delete_all, or #destroy_all
with a :conditions hash that includes a value object assigned to an
attribute key which corresponds to an AggregateReflection created by a
call to ActiveRecord::Base.composed_of. Oh my!
If you're interested in having this functionality, or are otherwise
using or have used "composed_of" in your models, please take a look at
and try out my patch.
For more details: