3 options

1-Fiddle with the RPM command line options to either force an install or overwrite system files (NOT RECOMMENDED AT ALL, but an option for those who know what they're doing, think it will work, and are prepared to rebuild their system if/when it gets DESTROYED. In this specific case I suspect it would be a disaster/problem and should be avoided)

2-Try to find if someone has an RPM build of dosbox for Fedora Core 4 elsewhere
For example I like to look for RPMs at
http://www.rpmfind.net/linux/RPM/
or http://www.rpmseek.com/index.html
and use the search function to find the package I'm looking for
http://rpmfind.net/linux/rpm2html/search.php? … x&submit=Search+...
And then look for the right distro/version/architecture
Fedora 4-i386
http://rpmfind.net//linux/RPM/fedora/4/i386/d … .63-6.i386.html
Fedora 4-x86_64
http://rpmfind.net//linux/RPM/fedora/4/x86_64 … 3-6.x86_64.html
For those don't like or use RPMs, they could always try
http://www.tuxfinder.com/
It has other formats, but I haven't used it in a few years so I don't know how well it's working of late.

3-Build from source

My personal preference for dosbox is (3) but I suspect you'd prefer (2). (If you try (1), do not say I didn't warn you)