I need to convert a huge application, with more than 1500 function points, from PHP with lots of forms using QuickForm, to Ruby on Rails.
There are a equivalent of QuickForm in RoR?
I am not sure what you mean by saying "equivalent", but there are solutions for Rails that make writting forms fun. Or at least less dull and painfull.
For example you may take a look at: Formtastic: https://github.com/justinfrench/formtastic SimpleForm https://github.com/plataformatec/simple_form
Just remember to pick correct branch, if you go with Formtastic (Ruby on Rails 2.x or 3.x)