greylist warning message and env_To

It looks like dccm/dccm.c is the only place to change the "temporary 
greylist embargoed" error message, am I correct?

I too, like Gary, is seeing more and more mail servers rejecting 
messages flagged as 452 type errors. I want to change the error message 
to a web page where I can report them back to us.

I like the concept of greylisting, though many customers still report > 
8 hour delays on mail delivery.  I think many mail servers have "fail 
once, fall back a long time" option for outbound mail.   Perhaps they 
see what I do that mail that doesn't get delivered immediately will 
generally never get delivered (bad bounces, etc).

Also, will greylisting work with Env_To whitelisting and/or sendmail's 
delaychecks?  We're trying to open up a few accounts to accept anything, 
anytime, regardless.

tim