Since upgrading from Angular 1.3.0 RC-2 to RC-3 the hash-sign in my links generated by ui-sref has disappeared. The link is clickable and the state transfers happens correct
That's a known issue. It's fixed in master. https://github.com/angular-ui/ui-router/issues/1397
master
Angular 1.3 changed the HTML5 mode API, and UI-Router has to support either API.