sendmail virtual

[GateKeepeR News <gatenews omnicast net>]

Running Redhat 5.2, full errata, w/ sendmail 8.9.3. We are also running
virtual domains, and that works great except for one thing. I can send
an email to user@<insertanyofourdomainshere> and it will send to that
user. For example:

Local domain: myisp.com
vdomain1: business.com
vdomain2: retailbusiness.com

local domain user: jsmith

So the address for the user is jsmith myisp com, but I can also send
e-mail to jsmith business com and jsmith retailbusiness com  Is there
any way to prevent this? I would rather be able to specify ONLY the
users who's e-mail I want forwarded to which domain. TIA

	-Bryan