Blog Types Error When Saving Changed Blog Type

Hello,

The following error appears when changing and saving a blog type in the admin area; however, it appears the change is saved.

Warning: join() [function.join]: Invalid arguments passed in /home/content/42/7040342/html/wp-content/plugins/blog-types/blog-types.php on line 668

WPMU 3.0.4

Thanks,
Phil D