Yourls URL showing username and password to Yourls installation

I’ve got WP to Twitter setup and working fine alongside a Yourls installation on a subdomain from the main site.

The funny thing is though that when looking at the post in wordpress, the Yourls URL contains the username and password to the Yourls installation?!?

Is this how it’s supposed to work, or have I got the wrong end of the stick?

Below is a copy of the url taken from the post – I’ve substituted the login info with * btw!

The previously-posted YOURLS URL for this post is http://i.strongti.es/nurturing, which points to http://strongti.es/a-nurturing-social-network/?utm_source=twitter&utm_medium=twitter&utm_campaign=twitter&action=expand&shorturl=http%3A%2F%2Fi.strongti.es%2Fnurturing&format=json&username=*****&password=****.

http://wordpress.org/extend/plugins/wp-to-twitter/