help me, a broken package can be removed

[ning luwen]

error from synaptic:
E: flashplugin-installer: subprocess installed pre-removal script
returned error exit status 2

try:sudo dpkg --force-all --remove flashplugin-installer
return:
(Reading database ... 194602 files and directories currently installed.)
Removing flashplugin-installer ...
update-alternatives: error: no alternatives for iceape-flashplugin.
update-alternatives: error: no alternatives for iceape-flashplugin.
dpkg: error processing flashplugin-installer (--remove):
 subprocess installed pre-removal script returned error exit status 2
postinst called with argument `abort-remove'
dpkg: error while cleaning up:
 subprocess installed post-installation script returned error exit status 1
Errors were encountered while processing:
 flashplugin-installer


i don't know how to remove it.
(ps: this happened when I upgraded my system to ubuntu 9.10 from 9.04
using  ubuntu 9.10 RC alternative iso.)