Thanks for keeping me updated. It appears that the problem is not necessarily tied to the type of validation either, as I was trying to validate "mm/dd/yy" on mine.
I typically will have the input and such and then I run a function I created when it actually gets inserted in the database to put the date in database format (yyyy-mm-dd).
But I also tried several different validation configurations and kept getting the preg match error. The only time I could get my page to continue through working was to just remove the line for the server validation altogether and just leave the client validation.