[jQuery] Bad Syntax? $('body').append('<input value="' + multipliedweight + '">'); breaks script

[jQuery] Bad Syntax? $('body').append('<input value="' + multipliedweight + '">'); breaks script


A test page is located <a href="http://www.procycle.us/
test.html">here</a>.
I'm attempting to insert an extra hidden input field with the extra
weight whenever an item in our shopping cart page has a quantity of 2
or more. Problem is this specific part of the code:
$('body').append('<input type="hidden" name="weight" value="' +
multipliedweight + '">');
causes an externally linked array named domesticpriorityarray to
become undefined according to firebug. If I remove the problem code:
$('body').append('<input type="hidden" name="weight" value="">');
then the script works properly.
I'd appreciate any insight you can give. Thank you!