The standard yum.cron exclude clause permits multiple lines:
-----------------------
exclude = fee fi fo fum
   foo bar baz
-----------------------
The /etc/yum.d/yum.cron.excludes  file is not so permissive; the second
line causes a sed script around line 151 in /etc/cron.daily/yum.cron to
barf.  I could fix that with an inline perl script, but I don't know
how to conditionally concatenate lines with the tools already in the
script, and hate introducing another dependency.

So the easiest thing is, don't use multiple lines in the excludes file!

Keith

-- 
Keith Lofstrom          [log in to unmask]         Voice (503)-520-1993
KLIC --- Keith Lofstrom Integrated Circuits --- "Your Ideas in Silicon"
Design Contracting in Bipolar and CMOS - Analog, Digital, and Scan ICs