Swiss-German has dative and accusative case-marking for its objects.
In the sentence "I gave him the book," "him" must be marked as dative and "the book" must be marked as accusative. It's clear that "him" is the indirect object since you can rewrite the sentence as "I gave to him the book."
But the verb "help" requires it's subject to have a dative case, which semantically makes sense since the object is the beneficiary of the action in the sentence. But syntactically, it seems to be of a different flavor, one which I don't understand with my rudimentary knowledge of generative syntax.
First of all, you can't rewrite "I helped Hans build the house" using "helped to Hans." Second, it looks like "help" is taking an independent clause as an argument with no explicit or even implicit complementizer, but the fact that "Hans" is marked (in Swiss German: "em Hans") makes it seem as though it is just taking "Hans" as an argument. Is there any discussion in generative syntax or elsewhere about this? Do you know of any references that might help me answer similar questions?
By the way, if you couldn't already tell, I started thinking about this because of this paper: http://www.eecs.harvard.edu/shieber/Biblio/Papers/shieber85.pdf