Register w/ Facebook + Anti Splog Asirra Fatal Error

wpmu-dev-facebook plugin + anti-splog.

When we try registering with facebook we get a fatal error:

http://screencast.com/t/8bZZxlJy ->
Fatal error: Cannot redeclare startelement() (previously declared in wp-content/plugins/anti-splog/includes/asirra.php:41) in wp-content/plugins/anti-splog/includes/asirra.php on line 41

How can this be solved, please?