Validating options and custom fields

Hi,
I'm hoping for some advice on the best way to apply some validation to options and custom fields. My situation is this: I have an option for personalization with two choices, no and yes. I then have a custom field for entering the personalization name. If the customer chooses yes to personalization, they enter the name in the custom field and all is well. However, if they select no to personalization, there is currently nothing stopping them from still entering a name to be embroidered in the custom field and submitting the order (without accepting the $10 additional charge). Make sense? I can handle this easily in a simple web page with an onchange event on the select list and a javascript function to control the custom field, but I am wondering what the best approach to this within the PC framework would be.
Any ideas?
thanks in advance,
gjk

Thanks, but I am not using BTO - would be overkill for my simple personalization options. I have handled it through javascript by editing the asp code to add the onchange calls where needed - just wondered if someone had a more elegant/scalable solution for the base product.

Hi,

Hello,

Can you please share with me as well?  I'm having the same problem.

Thanks!