Problem with WordPress Mobile Admin

Hi I cant get my WordPress Mobile Admin to work. Run a WPMU 2.8.5.2 installation.
Ive installed the plugin and entered the wapple-key. But when I login to the admin site it shows the usual admin interface and not the mobile admin interface.
One thing I wonder: the installation runs blogs like:
http://xxxx.xx.nu/blog1
http://xxxx.xx.nu/blog2
and so on.
In wapple admin i put http://xxxx.xx.nu/ as domain for the key. Is that correct? I would like to activate the plugin for more than one blog without having to register for a new WappleKey every time.

Thanks for any help w this!