jQuery [Validation Plugin] - Dependent Require

jQuery [Validation Plugin] - Dependent Require

Hello,

I have a form that is validating fine using the jQuery Validation plugin, however there is one field I need to do something slightly different with.

I have a normal text input field field called "Expenses" and a textarea field called "Comments". If "Expenses" has a number in it, I need the user to type something into the "Comments" field before the form can be submitted, and generate an error message as appropriate.

I've Googled this and had a browse through some forums but can't find anything to point me in the right direction. Any help would be much appreciated!

Adam