Comment 6 for bug 131865

Same problem here via the update manager.

I retried from the command line and apt-get now wants to uninstall thunderbird and enigmail!

 sudo apt-get install flashplugin-nonfree
[sudo] password for ajft:
Reading package lists... Done
Building dependency tree
Reading state information... Done
flashplugin-nonfree is already the newest version.
The following packages were automatically installed and are no longer required:
  thunderbird enigmail
Use 'apt-get autoremove' to remove them.
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
1 not fully installed or removed.
Need to get 0B of archives.
After unpacking 0B of additional disk space will be used.
Setting up flashplugin-nonfree (9.0.48.0.0ubuntu5) ...
/var/lib/dpkg/info/flashplugin-nonfree.postinst: line 107: syntax error near unexpected token `do'
dpkg: error processing flashplugin-nonfree (--configure):
 subprocess post-installation script returned error exit status 2
Errors were encountered while processing:
 flashplugin-nonfree
E: Sub-process /usr/bin/dpkg returned an error code (1)