Overlap function for hstore?

Hi,

I'd like to get an overlap function similar to '&&' but for key-value
pairs of hstore!

This underfits:

postgres=# select hstore_to_array('a=>1,b=>2,c=>3'::hstore) &&
hstore_to_array('a=>2,d=>4,b=>2'::hstore)

...because array overlaps op takes every element (even 'a' or 2 alone)
and doesn't test for key and value together like in 'b=>2'!

Any clever ideas?

Yours, Stefan