once again having a people picker not resolving active directory users of a two-way-trust domain. So we configure the picker as described e. g. in one of these how to configure picker blogs.
Having done this we now see that the "old" (2010-style) picker resolves the users but the 2013-person-or-group-field does not show up the users in the search result box (it's only showing users of the farm domain). But if we write the e-mail address of the user to the field and confirm the user is resolved correctly.
So, what are we missing? Does the picker configuration really do the same in SP 2010 & 2013?