I drop the php script in my /wp-content/plugins/ directory, comes up fine under the plugins menu in wordpress, I activate, and then when I go to my widgits, it's not there...when I try to manually add the <?php twitter_messages(''); ?> tag, it just renders the page to the point where the twitter_messages tag is, then stops, so half the page is blank. That was a really long run-on sentence.
Using Wordpress 2.5 on Yahoo! Small Biz servers (which I believe is PHP4 ish).