Some clever guy at RedHat has decided that we're all using X-terms out here and nobody should ever use a VT-100. This being the case, they've mucked up the way man pages display on a VT-100. All of the boldfaced and highlighted characters come out broken, etc. Here's how to fix it.
/etc/man.config or /usr/etc/man.config:
Change the config file (wherever it is kept) to read something like:
NROFF /usr/bin/nroff -Tascii -c -mandoc
Make sure you use "-Tascii".
Note that under later versions of RedHat (and CentOS), the nroff command is actually a shell script that invokes groff. And, bonus, they decided to throw away the "-T" option. So, you can use "-Tascii" until you're blue in the face and nothing happens. Instead, you should use the following, if your nroff is actually a shell script:
NROFF /usr/bin/groff -Tascii -c -mandoc 2>/dev/null