Blocks

Yes, there is. Unfortunately there is no user interface for it yet but it's still very simple.

Open /lang/XX/moodle.php where XX is the language you are using. Find:

$string['firstdayofweek'] = '0';

and change the 0 to any number you want. 0 = Sunday, 1 = Monday, ... , 6 = Saturday. That will change the default for all users who are using this language.

Jon