I'm not the only one who has a problem with Back button. Working on new mobile site, I started experiencing problem with Back Button presentation using ListView. It's completely gone when viewing a nested list submenu. I found a good solution on StackOverflow.com. It's quite sophisticated and smart code-snippet, which work very well.
Here it's
<script type="text/javascript" language="javascript" type="text/javascript">
$(':jqmData(url^=home)').live('pagebeforecreate',
function (event) {
$(this).filter(':jqmData(url*=ui-page)').find(':jqmData(role=header)')
.prepend('<a href="#" data-rel="back" data-icon="back" data-theme="b">Back</a>')
});
</script>
Replace MYPAGEID with the ID of the page containing the list.
It should be added after jQuery initialization.