Remove function from a plugin

Hi,

I have a child theme and integrating a e-commerce plugin.
Would like to remove an certain function from that plugin because it’s messing up theme styling.

The function is called ‘jigoshop_output_content_wrapper’ and is adding a ‘div’ to my template files:

else echo '<div id="container"><div id="content" role="main">';

How can I completely remove this function?

This should be working but I don’t know where I can find the so called tag:

<?php remove_action( $tag, $function_to_remove, $priority ); ?>

http://codex.ww.wp.xz.cn/Function_Reference/remove_action

Guido