Need suggestions...

There is no postback to enable/disable controls such as TextBox or CheckBox?using?javascript in the client side,but postback in server side.If the validators can not be enabled/disabled in the client side through javascript,you need to enabe/disable it in the server side.I think it should be enabled/disabled in the client side and?maybe you need to register client script in the server side(ScriptManager.RegisterStartupScript).
Try to take a look at the following sample codes to work withAjax:RequiredFieldValidatorfor reference.
http://www.mathertel.de/AJAXEngine/ViewSrc.aspx?file=~/S03_AJAXControls/ValidatorDemo.aspx
http://ajax.asp.net/docs/mref/75d6494c-beed-1b07-22d6-894095d5b2cd.aspx
Wish the above can give you some helps.

What I was looking for was: ValidatorEnable(control,enabled). Microsoft had it out there for me already, I just had to find it.

Its found in the WebResource.axd javascript file for validation. Works great. Just give it the validation control's clientID and whether its enabled or not.