How do you feel about editing the code?
$altclass = ( ' odd' != $altclass ) ? ' odd' : ' even';
This line sets $altclass to either ‘ odd’ or ‘ even’ depending on whether it was previously odd, but if it was never previously set to anything then PHP reports this error.
Replace the line with
$altclass = ( isset($altclass) && ' odd' != $altclass ) ? ' odd' : ' even';
and PHP won’t mind if it wasn’t previously set.
It happens again at line 174, so you’ll need to edit both instances.
