drupal_add_js gets squashed

jquery is present on all pages in the theme, but my jquery (very simple one-liner:

$document.ready(function() {
$('tr:even').css('backgroundColor', '#e8e8e8');
});

keeps giving me the 'document is not defined' error- i read that this can be caused by the template requiring pre-processing, and i tried adding my js file via drupal_add_js in nitobe's template.php as well as in nitobe.info, and keep getting the same error. any ideas on how to force jquery to load up sooner?