maximized windows move workspaces when screen size changes

I use my laptop in two setups: by itself with its 1440x900 built-in panel, and docked/closed using an external 2560x1440 monitor only. (So only one active screen in both cases) I use multiple unity workspaces, with (for example) a maximized browser window in the top right workspace and a emacs maximized in the lower left workspace.

I find that if I suspend while docked and then resume after undocking (so I am switching from 2560x1440 -> 1440x900 screen), everything mostly works except that my maximized windows unpredictably change workspaces; I might end up with the browser and emacs stacked on top of each other after this transition.

It seems that a sensible heuristic would be that if I maximized a window in a particular workspace, then the window should stay maximized in the same workspace after a screen size transition.

ProblemType: Bug
DistroRelease: Ubuntu 13.04
Package: unity 6.12.0daily13.02.08-0ubuntu1
ProcVersionSignature: Ubuntu 3.8.0-6.13-generic 3.8.0-rc7
Uname: Linux 3.8.0-6-generic x86_64
ApportVersion: 2.8-0ubuntu4
Architecture: amd64
CompizPlugins: [core,composite,opengl,compiztoolbox,decor,vpswitch,snap,mousepoll,resize,place,move,wall,grid,regex,imgpng,session,gnomecompat,animation,fade,unitymtgrabhandles,workarounds,scale,expo,ezoom,unityshell]
Date: Tue Feb 19 08:41:24 2013
EcryptfsInUse: Yes
InstallationDate: Installed on 2012-01-04 (411 days ago)
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Alpha amd64 (20120104)
MarkForUpload: True
SourcePackage: unity
UpgradeStatus: Upgraded to raring on 2012-12-11 (70 days ago)