__getattr__ functionality for modules?

[Stefan Franke]

Is there a way to achieve for modules what overriding __getattr__ does
for classes?

My problem: I want an infinite number of identifiers appear as if they 
were defined in the global namespace.

The identifiers have structured names (say, id2m5, id2m6, id3m2, ...),
and I'd like to generate the respective values on the fly and cache
them for subsequent lookups.

If they were attributes of an object it would be trivial, but how do I 
achieve this for name lookups in the __main__ (or any other) module?

Stefan