cron.php fails to load category.inc

I got this error this afternoon:>

Fatal error: Call to undefined function: category_node_get_categories() in /var/www/wlp_play/modules/category/category.module on line 1312

I was able to fix it using:

cvs diff category.module
Index: category.module
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/category/category.module,v
retrieving revision 1.45
diff -r1.45 category.module
1311a1312
> include_once('category.inc');

But don't think this what is intended. Thanks!