Im trying to uninstall directory server 5.2 because it failed with a
configuration error, and when I try to reinstall it shows all
components to be installed greyed out as 0 bytes so I cannot continue
the install as mentioned in:
http://swforum.sun.com/jive/thread.jspa?messageID=210740

They suggest using prodreg to uninstall or edit /etc/ds/versions but
prodreg fails with:

Exception in thread "main" java.lang.NoClassDefFoundError:
uninstall_dirserver

and I do not have a /etc/ds/versions file.  Please help.

taking out DS entries from /var/sadm/install/productregistry fixed it.