Fatal error: Call to a member function get() on a non-object

I’m building a website in WP 2.7 and tried to use the events category plugin, because it offered the exact functionality I was looking for. Now I know this plugin isn’t supposed to be compatible with the 2.7 version (yet?), but I tried it anyway and it worked like a charm… for some time.

Then I got this:

Fatal error: Call to a member function get() on a non-object in ../wp-content/plugins/events-category/events-category.php on line 270

I can’t think of anything that would justify a fatal error like this… I had just finished writing a test comment, when it popped up. And even after deleting the comment (and the post), the error remained. If I deactivate the events category plugin, the error is gone. But then my events page isn’t working like it’s supposed to either 😉

This is what it says on line 270:

if($wp_query->get('name'))

And is part of this piece of code:

if(empty($catIDs)) {
		#This conditional is needed because if going to non-existent post under events category, it will think
		#   that it is not single
		if($wp_query->get('name'))
			return false;

		$category__in = $wp_query->get('category__in');
		if(!empty($category__in))
			$catIDs = $category__in;
		if($wp_query->get('cat'))
			$catIDs[] = (int)$wp_query->get('cat');
	}

Has anybody got any idea what has happened here? I’m no php wizard, so I’m having a hard time understanding this. Any help or explanation is very much appreciated. I would love to understand this and get it working again.