Validates_* requirements

Hello,

I have the following in my user.rb model:


validates_numericality_of :zipcode, :message => " =>
ZipCode must be a number"

validates_length_of :zipcode, :minimum => 5, :message => " => Please enter a zip code at least 5 numbers in
length"

validates_uniqueness_of :email, :message => " =>
Email address already taken, please choose another"

validates_uniqueness_of :username, :message => " =>
Username already taken, please choose another"

validates_length_of :password, :minimum => 5, :message => " => Password Can Not Be Blank"

validates_confirmation_of :password, :message =>"Passwords do not match
"

However, the password length and confirmation just dont work. Are
there any specific requirements that would prevent this from working ?

thanks
adam