PHP errors since 2.0.3 upgrade

I have come across two PHP errors since upgrading one of my sites http://www.helengrace.co.uk to WP 2.0.3

First of all:
On the index page, where it says “Site Updates” I use this code:


<?php
if (empty($_SERVER['QUERY_STRING'])) {
$cat = '24';
}


…to make posts from the category “updates” show up there. At the moment, since I updgraded, it’s showing ALL my posts from ALL categories, which is obviously not what I want.

Secondly:
On some of the pages that are WP-powered I’m getting this error message:

“Fatal error: Call to undefined function: _e() in /home/helengra/public_html/reviews_mab.php [or whatever the name of the page may be] on line 29.”

This happens on all the news pages and many of the media pages. I assume these issues are related to the upgrade because I never experienced anything like this before. Can anybody help?