[CentOS] public Key Problems after Centos 4 -> 5 update.

Thu Oct 25 18:06:59 UTC 2007
Robert Slade <centos at likley.co.uk>


I have just updated my system from Centos 4 to 5 using the DVD. When I
try to update using Yum, it gets so far then I get:

"Public key for tomcat5-jsp-2.0-api-5.5.23-0jpp.3.0.2.el5.i386.rpm is
not installed"

How do I get the key and install it?