Rails don't supoort mysql bigint?

Rails
1

hi

rails 1.2.6 mysql 5

table:infos
fields:id ,bigint(20), AUTO_INCREMENT =90000000013
name,varchar(255)

info_controllor.rb
def add
@info = Info.new
@info.name = “ddd111”
@info.save!
puts “id:”,@info.id.to_s
end

run…
id:-194313203

why?rails don’t supoort mysql bigint?

thx~~~