[rt-users] can't write to '/var/log/rt2/rt.log8'

[Phil R Lawrence]

RedHat 8.0
suidperl is installed:
   # ls -l `which suidperl`
   -rws--x--x    2 root     root        77025 Sep  2 00:14

When I email a ticket, sendmail correctly pipes:
"|/opt/rt2/bin/rt-mailgate --queue student --debug --action correspond"

but here is the error:
Effective User 8 (Real User 8) can't write to '/var/log/rt2/rt.log8': 
Permission denied at /usr/lib/perl5/site_perl/5.8.0/Log/Dispatch/File.pm 
line 72.
554 5.3.0 unknown mailer error 13

(I added the user info.  User 8 is 'mail'.)

Any help?
Thanks,
Phil R Lawrence