Search Submit Button (IMG)

Hey all, I’ve been looking round, and I cant see any topics on the subject, so here goes:

How do you change the “Submit” button by the search textbox into an image? there is a normal way to do it, and I’ve used it before in other websites. But when I try the same method with the “Searchform.php” File it dosen’t work.

This is the line of code I tried, and I’m testing within Localhost.

<input type=”image” src=”images/submit_button.gif” height=”20″ width=”41″ border=”0″ alt=”Submit Form” id=”searchsubmit” value=”Search”>

Here is the default code, before I changed it:

<input type=”submit” id=”searchsubmit” value=”Search” />

Any help would be greatly apprichiated, Thanks!