[Dancer-users] Question about Dancer::Plugin::ValidateTiny

Dear dancers, I'm building a web application and need to use some forms. I'm using Dancer::Plugin::ValidateTiny to validate de parameters that the web browser send in every request. It's very easy to use, but I have found a limitation and doesn't know how to overcome it. The form i'm working now is for creating a new user, so it has four fields: "username", "password1", "password2", "email". I'm doing the usual checking, but i can't find the way to implement the folloging rule: "username" and "password1" can't be equal. Is there a way to do this? Thank you, Fontardion