If you ever find yourself needing to selectively disable an asp.net validator through javascript, you can do the following (in 2.0, not sure if this exists in 1.x):
function doSomething()
{
var myVal = document.getElementById('myValidatorClientID');
ValidatorEnable(myVal, false);
}
Quick and easy! Sadly, not as easy to find through Google, so hopefully this post will help that. :)