"Vacuum Recommended" dialog has no "no" option

[Shish]

I've just had a "Vacuum Recommended" message pop up on my screen, the only available options are "Vacuum" and "Ok"

Firstly, there are two different UI styles (It should either be "Vacuum / Do not vacuum" or "Ok / Cancel"); and secondly, both options seem to suggest that if I click them then a vacuum will be run. The "Vacuum" button suggests this slightly stronger, so I would guess that "Ok" means "Do not vacuum" - but if "Ok" means "do not vacuum" then what does the "Cancel" button do? It is greyed out, but it is the only button that seems to be what I want...

ProblemType: Bug
DistroRelease: Ubuntu 11.04
Package: pgadmin3 1.12.2-1
ProcVersionSignature: Ubuntu 3.0.0-4.5-generic 3.0.0-rc6
Uname: Linux 3.0.0-4-generic x86_64
NonfreeKernelModules: nvidia
Architecture: amd64
Date: Tue Aug 23 10:46:34 2011
EcryptfsInUse: Yes
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Release amd64 (20101007)
ProcEnviron:
 LANGUAGE=en_GB:en
 PATH=(custom, user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: pgadmin3
UpgradeStatus: No upgrade log present (probably fresh install)