Does CA uses SDM to manage our cases? If yes, it's a multi-site multi-timezone Company. How do they manage that? Chriss can you ask internally?
Timur, If CA can't answer, ever thought on not relying on pdm_mail at all? You can always trigger events instead of notification rules. I personnaly send a lot of mail with PAM instead of SDM. You can always use an external java/PS/perl app if PAM's not avaible.
I know this will not be easy. Getting the "to" of a manual notification sounds like a good challenge but surely feasible.
Let me know if you want to go that way, i can search with you on my spare time.