Several of our Solaris sparc RPM 2.5.6 machines
dumped core as we tried to upgrade a package.
It was one particular package which caused the core dump
and this only on some machines.
The coredump occured very early in the installation (but I
could hear the disk on the ftp site moving).
The problem went away when we did an 'rpm --rebuilddb', so
I have a workaround.
This problem appears to be solved.