Is there any way to have AIX CacheFS working in write-back mode?

I wish for writes to the cache to take place locally and have the system
transfer to the server on the backend, thus giving write performance. I
realize this would introduce possiblilty of inconsistancy in the cache
vs. server, if the write were to succeed on the cache and not succeed on
the server for whatever reason, in this case the applicaiton writing
would not be informed of such a failure.

I have tried the non-shared mount option which causes writes to both
local and remote when you write, but it still waits for the remote write
to finished before releaseing the application doing the writing.

It doesn't even have to be CacheFS, but I've looked at various other
technologies, but none seem to suit my needs. I want read and write
performance of a remote filesystem. No files are ever deleted, only new
files written.

Thanks for any suggestions.