Small PHP script with Ajax tweak

I have a webform that works by means of ajax. The users fill out the form and click a 'register' button. When they have entered their details and clicked 'register' it will send me an email, and display another page thanking the user. I want it only to move to the next section (email and thankyou page) if they have firstly, filled out an email address containing an 'at' sign, and secondly - if they have entered an 'authorisation code'. I have the authorisation code setup, whereby it generates an auth code each time and they can enter it in a box. I just want this to work correctly, i.e - only go next if they have entered it correctly. The form already uses an ajax script and reports back if the username is taken ect on the form without having to reload the page. I want this same method using with the 'at' sign, and the authorisation code. Let me know if you are up to the task. Kind regards. ## Deliverables 1) Complete and fully-functional working program(s) in executable form as well as complete source code of all work done. 2) Deliverables must be in ready-to-run condition, as follows? (depending on the nature? of the deliverables): a)? For web sites or? other server-side deliverables intended to only ever exist in one place in the Buyer's environment--Deliverables must be installed by the Seller in ready-to-run condition in the Buyer's environment. b) For all others including desktop software or software the buyer intends to distribute: A software? installation package that will install the software in ready-to-run condition on the platform(s) specified in this bid request. 3) All deliverables will be considered "work made for hire" under U.S. Copyright law. Buyer will receive exclusive and complete copyrights to all work purchased. (No GPL, GNU, 3rd party components, etc. unless all copyright ramifications are explained AND AGREED TO by the buyer on the site per the coder's Seller Legal Agreement). ## Platform Linux hosting, ajax, PHP