Unexpected exceptions from Scheme Services

While trying out the services provided by SchemeServices i noticed that i always get the following exception back:
java.lang.IllegalArgumentException: PermissionType passed to this function must a global permission, 23 is not

As i do not have admin or project admin rights i was expecting to get a permission exception. The error message is also a bit cryptic. I think it may be missing a 'be'. It would also be nice if it used the permission name instead of the id.