JQuery :: Search Form Remove Value On Click And Add The Value Back On Click Off?

I've a function for my search form. Basically when you click on the form box where it says "Enter your search here" this value disapears when you click in the box. When you click out the box it re adds the value. It works if you click return on the keyboard and performs the search no problem. However if you click the search button with the mouse it removes the search term and replaces it back with "Enter your search here". This obviously will not return the search.

Anyone know how I can fix this so this does not happen on the mouse click?

I've used jsfiddle to add the html and javascript but it is not working in there, but works if you add it to dreamweaver and look at it within a browser. [URL]

This is the code:
<script type="text/javascript">
function make_blank()
{

[Code]....