Checking an XML database

I would like to create a form where a person can enter their product serial # into a field and it will check to make sure that serial number exists within an XML database in order for them to submit the form.


How would I go about doing that? Keep in mind I'm using all custom chronoforms.

Thanks!

Hi DL_ChronoFormsUser,

What is an XML database and how do you access it from Joomla!?

Bob