I've got this :

<a id="m0" href="#" title="Find Home Health Agencies"><img src="media/graphic/menu/agencies_s.png" alt="Find Home Health Agencies" /></a>

How can I get the src of the image so I can swap it with an onmouseover?

Also, why when I do some javascript in Firefox, sometime, the browser goes crazy like refresh does not work or I can access others tabs ??