is_in does not find surrounding areas for some input sets containing redundant nodes

[Ecumenopolis]

Example:

Nodes 151615580 and 151591244 have the same coordinates in Tekamah, Nebraska.

These two query return the same output set, consisting of one closed way and seven areas.

node(id:151615580); is_in; out ids; node(id:151591244); is_in; out ids;

But if they are both in the input set, the output set contain only the way -- the relation-based areas aren't found.

node(id:151615580,151591244); is_in; out ids;