I have just switched to Fedora 7.0; SWAT will not accept the "root" user id and password via the "localhost:901" browser interface. I suspect it is not finding the system password file it needs. The swat interface worked fine under fedora 6; I have not configured my fedora 7.o installation any differently.
Solved this problem. SELinux firewall was blocking access to the system password files. Solution: temporarily set SELinux to "permissive"; use SWAT; reset SELinux to "enforcing" when done.