OT: Quick postfix question

[Kevin Miller]

I'm new to postfix, (making the transition from sendmail), and have a quick question.  In my main.cf, can I have multiple check_client_access lines?  Currently I have this one:
    check_client_access hash:/etc/postfix/rbl_override_whitelist
where I was whitelisting certain domains.  Then I realized I could also put in lines with REJECT rather than OK. 

It's largely cosmetic I suppose, as both REJECT and OK seem to work in the same file, but I'd rather have a whitelist and  a blacklist file similar to what we have in MailScanner, only at the MTA level.  Any issues doing that?

TIA...

...Kevin
--
Kevin Miller
Network/email Administrator, CBJ MIS Dept.
155 South Seward Street
Juneau, Alaska 99801
Phone: (907) 586-0242, Fax: (907) 586-4500 Registered Linux User No: 307357