useradd: cannot rewrite password file

["Kall, Bruce A." <kall mayo edu>]

All of a sudden I am getting this on my Fedora 2 system that has been up 
and running fine for some time when I try to add a new user with 
useradd.  All I can find in bugzilla is a NOTABUG reference (116391) to 
shadow.  Any suggestions on how to fix this?

Thanks