VB.net automatically populate the Trademark field with the current date as a Pre-build event

I was asked the the following question by a client. Can anyone help me with this? Thanks

"One thing I would like to be able to do is automatically populate the Trademark field with the current date as a Pre-build event.

Have you ever seen this done?  Or does VS11 allow you to do this?

 I’ve never tried any pre-build events and it looks more complicated than I’d hoped.

Ideally  once I knew how to update this field I could also get the Assembly version to increase every time I published the project