Simple form validation script
To avoid conflict with any other libraries, wrap your code using the jQuery function, and additionally call jQuery.noConflict();

The only conflict you may have is if somebody else imported an object named jQuery into the global namespace.

Reference: http://docs.jquery.com/Using_jQuery_with_Other_Libraries

Example:

jQuery.noConflict();
jQuery(document).ready(function($){
 //This is a jQuery function
 $('.myClass');
});