> 	sorry for vague question: are there any prior art for equal cost
> 	multipath support (like multiple rt_gateway), specifically in terms
> 	of modifications to routing socket messages?  if there's some code
> 	publically available, it would be nicer.

(Sorry, I don't reply for your question.:)
Don't you mean multiple FIB support in *BSD kernel? Or you includes
the one also?
--
Hitoshi Asaeda