pidgin stays running in top panel, but not in dock

[Alan Jenkins]

After closing the pidgin window, it stays running in the "notification" indicator in the top panel (the envelope icon).

But it doesn't show in the Dock. I have Pidgin pinned to the dock, so the icon is present, but the chevron next to it is missing. Also, I can't close pidgin by right-clicking on the pinned dock icon - not until I re-open the pidgin window.

Expected behaviour:
 - If pidgin can be running with no windows open, then I should be able to quit from it without a two-step process (opening a window first).

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: pidgin 1:2.10.3-0ubuntu1.1
ProcVersionSignature: Ubuntu 3.2.0-27.43-generic 3.2.21
Uname: Linux 3.2.0-27-generic x86_64
ApportVersion: 2.0.1-0ubuntu11
Architecture: amd64
Date: Tue Jul 24 14:40:28 2012
ProcEnviron:
 LANGUAGE=en_GB:en
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: pidgin
UpgradeStatus: No upgrade log present (probably fresh install)