apt-get upgrade problem with libenchant1c2a

[David Goodenough <david.goodenough@btconnect.com>]

I have a sacrificial machine that I keep upto date with sid every 
morning.  Yesterday and today I get an error:-

Calculating upgrade... Failed
The following packages have unmet dependencies:
 libenchant1c2a : Depends: aspell-en but it is not going to be installed or
                           myspell-dictionary or
                           aspell-dictionary or
                           ispell-dictionary or
                           hunspell-dictionary
                  Recommends: enchant but it is not going to be installed
E: Error, pkgProblemResolver::Resolve generated breaks, this may be caused by 
held packages.
Reading package lists... Done
Building dependency tree     

But apt-cache policy libenchant1c2a says:-

  Installed: 1.6.0-10
  Candidate: 1.6.0-10

so it should not need upgrading at all.

Also aspell-en is installed.

Is this related to Ubuntu bug  #1096669?  There is nothing in bugs.debian.org
that seems to fit the bill.

Any ideas?

David