IR refuses anonymous comments

I set up my permissions as follows

comment module                       anonymous      logged in
access comments                       checked        checked
administer comments	               blank          blank
post comments                         checked        checked
post comments without approval        checked        checked

However, with for a content-type with enabled inline-registration, I cant get anonymous comments. The system complains that username and password are not set.

I do manage to get there with http://drupal.org/project/anon_nodecreate, but a bit in a roundabout way. Too bad the module maintainers never worked something out.