More on inheritance and foreign keys

Hi,
after starting this thread
http://archives.postgresql.org/pgsql-hackers/2006-05/msg00222.php, I thought
I'd finally go for making foreign keys my own way instead of trying to patch
PostgreSQL. However, I've realized that managing foreign keys with my own
PL/SQL or C function isn't possible as I need DEFERRED checks which are
currently only available for foreign keys.

The solution to the foreign key problem seems easy if I modify PostgreSQL
implementation and take off the ONLY word from the SELECT query, but it's not
an option for me, as I'm developing a library, not an application. I'd like
many people could use it.

Would it be acceptable if one could add the INHERIT word when creating
foreign keys, in order to change the SELECT behaviour? Are there other
solutions to this problem?

Thanks.