Comment 2 for bug 975126

Cannot upgrade from firebird2.1-super to firebird2.5-super on 12.04 due to this:

root@server:~# apt-get install firebird2.5-super
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following extra packages will be installed:
  firebird2.5-server-common libfbclient2
Suggested packages:
  firebird2.5-doc
The following packages will be REMOVED:
  firebird2.1-server-common
The following NEW packages will be installed:
  firebird2.5-server-common firebird2.5-super libfbclient2
0 upgraded, 3 newly installed, 1 to remove and 0 not upgraded.
1 not fully installed or removed.
Need to get 336 kB/4,278 kB of archives.
After this operation, 10.4 MB of additional disk space will be used.
Do you want to continue [Y/n]?
Get:1 http://us.archive.ubuntu.com/ubuntu/ precise/universe libfbclient2 amd64 2.5.1.26351.ds4-2build1 [336 kB]
Fetched 336 kB in 1s (289 kB/s)
Preconfiguring packages ...
(Reading database ... 103354 files and directories currently installed.)
Removing firebird2.1-server-common ...
rmdir: unrecognized option '--ignore-if-not-empty'
Try `rmdir --help' for more information.
dpkg: error processing firebird2.1-server-common (--remove):
 subprocess installed post-removal script returned error exit status 1
Errors were encountered while processing:
 firebird2.1-server-common
E: Sub-process /usr/bin/dpkg returned an error code (1)