I've developed a theme in xtemplate for 4.6 and it worked great. I updated Drupal 4.6 to the latest build and now the theme broke. Below is the error I'm getting. I know it's a stupid question, but I would appreciate if you could give me a direction where to look, what to fix.

user notice: [XTemplate] parse: blockname [header.blocks] does not exist in /Library/WebServer/Documents/cbv2/themes/engines/xtemplate/xtemplate.inc on line 418.