file_column plugin

I'm using file_column to allow image uploads to a site.

Model Version 1
class Cimage < ActiveRecord::Base
  belongs_to :car
  file_column :image

  validates_presence_of :image
  validates_presence_of :text
  validates_file_format_of :image, :in => ["jpg", "gif"]
end

Model Version 2
class Cimage < ActiveRecord::Base
  belongs_to :car
  file_column :image, :magick => { :versions => { :thumb => { :size =>
'150x100' } } }

  validates_presence_of :image
  validates_presence_of :text
  validates_file_format_of :image, :in => ["jpg", "gif"]
end

Version 1 works fine for both jpg and gif, but Version 2 will only be
successful for gifs. I get a validation error that 'Image was not a
valid image,' every time a try to upload a jpg. Can anyone please
help shed some light on what the heck is going on here.