Today I’ve released jquery-validators, a jQuery plug-in with some predefined validators, but extensible to allow you to create field validations on change and keyup events. The plug-in runs individually for each field, without referring a specific form in the HTML. Also you can define custom validation function and custom messages, currently it supports English and Spanish messages, but you can setup your own messages on it. If the field isn’t valid for the validator, it will block the form identified by the form selector (written as jQuery selector string).
You can download it here: jquery-validators.
Entries 