UUCP under 3.0 is much improved over it's previous "incarnation" under 2.0.1. 3.0 uses HDB (for HoneyDanBer) UUCP instead of standard UUCP. Some nice things are bidirectional getty (also known as uugetty in other Unixs) which allows both incoming and outgoing communication over serial lines as well as better performance and reliability.
You may consider getting Alexis Rosen's "sendmail.cf" file for use under UUCP sendmail. This config file has been modified to allow UUCP and sendmail to work beautifully together. You may also want to consider simply installing smail to replace sendmail.
Under 3.0, be sure that you are running the latest version: 1.16. It can be found on aux.support.apple.com in aux.patches/supported/3.0. Be sure that you get the new dial.o on ftp.apple.com (pub/earlw/dial) to avoid breaking syslog. Under 3.0.1 (and later) all is OK.
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