After a botched install of a .ear file to my Oracle 9i application server, subsequent attempts to uninstall the application failed with the above error. Google was of no help; Metalink listed the problem, but offered no workaround. Although it would have been possible to just "get on with it" and use a different name, having a broken application listed among my installed applications was just too ugly.
Fortunately, I was able to remove the broken application by taking the following steps:
C:\ora9ias\j2ee\home\application-deployments\application-name\I removed these files and directories.
C:\ora9ias\j2ee\home\applications\application-name\
C:\ora9ias\j2ee\home\applications\application-name.ear