Submit Form when User hits 'Enter' key

I have a login page with 2 input fields and an image that the user currently clicks to submit the form. I want the user to be able to hit enter and then a vbscript sub-routine is called to verify the information in the form. If the information is verified, then the form get submitted. Can someone tell me how to do this? I know that if I had a button it would be easier, but I am need to use an image instead.

Thanks!

Do a search on google, there are numerous examples on how to do this.

I've searched on Google and have found examples. I am having a problem with the onmouseout and onmouseover events. I have tried it a couple different ways:

1) <input type="image" src="Login.gif" name="Login" onmouseout="document.frmMenu.Login.src='Login.gif'" onmouseover="document.frmMenu.Login.src='Login_mo.gif'" id="Login" style="cursor:hand">

2) <input type="image" src="Login.gif" name="Login" onmouseout="Login.src='Login.gif'" onmouseover="Login.src='Login_mo.gif'" id="Login" style="cursor:hand">

However, I keep getting errors on the page saying that the object isn't supported. I also want to add an onclick event to do some error checking.

using [this] will help u.

<input type="image" src="Login.gif" name="Login" onmouseout="this.src='Login.gif'" onmouseover="this.src='Login_mo.gif'" id="Login" style="cursor:hand">