I haven't done this in a long time. Hopefully, someone with more knowledge will answer, but you might have to do something in /etc/httpd/conf.d--there may be a file in there that needs editing.
Other things to try.
http://ask.fedoraproject.org/questio...via-my-browser
This also looks promising.
http://dicas.titomiguelcosta.com/?p=45
I'm not sure what searching you may have done on your own, but these both came up googling phpadmin on fedora
Note that I didn't even google it correctly, leaving out the "My"