I installed Netbeans 5.5 and 6 without problems. If you are installing the Netbeans - Java pack, you will get an error because Sun-java has problems with libawt.so library in fedora, but this can be solved installing java rpm from sun and Netbeans in separated way.
What error you got?
Pietro Pesci Feltri
PowerBook 15" G4 and
MacBook Pro 17" Intel Core 2 Duo
Intel I5 Desktop