how to hack the validationsummary control

I have a validationsummary control on my page but the client wants the error message to show up in a colorbox type dialog box. I can't find a开发者_JAVA技巧ny way to get to the error message of the summary so I can show it in a colorbox. Also, if someone knows how to get the error message, how do I hook into it's change or update method to know when to display the colorbox? Thanks.