[Typo3-shop] zk_products : strange button behaviour

[Rob De Vries]

This may not be the right place to ask this (and maybe my html knoldege 
fails here):

I have the following buttons in my shop:
an image button:

<input name="products_info" type="image" 
src="fileadmin/template/shop/proceed.jpg" alt="proceed" 
onClick="document.getElementsByName('basketform')[0].action='###FORM_URL_INFO###';" 
/>

and a regular button

<input type="Submit" name="products_info" value="Proceed" 
onClick="document.getElementsByName('basketform')[0].action='###FORM_URL_INFO###';" 
/>

now the regularbutton works fine in Firefox but the image buttons fail 
to work in IE, Opera, Netscape etc ...

can anyone give a clue what is going on here? what am I doing wrong?

tnx

rob