infinity progress circle during login time freezes

[Igor Hipólito Vieira]

What I expected to happen:
If you set your Ubuntu to ask for password before the system start, of course you will be able to choose a user, if this user is selected you can type the password and then click on symbol that looks like ">" or pressing the Enter key, after that this symbol will disappear and a infinity progress circle will replace it, this circle should flow/circulate.

What happened instead:
That's the problem, in my version of Ubuntu, 13.10, it doesn't happens, it is/looks frozen and the only thing that moves is the mouse cursor, you also can't iterate with any of the system tray options. Also I remember to have the same problem with 12.10 and 13.04, but when I switched to 13.04 and 13.10 I did a clean install (removing the older version partition first).

Possible solution (I'm just a noob):
The circle probably freezes, because when the login application access the "database" (in which contains the user password that will be compared with the one entered by the user) uses the default thread (like in computer programming thread), I know that when you perform a task in programming and it takes too long to be finished the GUI of this program usually freezes because you did not started this task in another thread. I think, if this is the problem, that the solution would be performing the task that "query the database" in another thread.

Description: Ubuntu Saucy Salamander (development branch)
Release: 13.10 (64-bits)

ProblemType: Bug
DistroRelease: Ubuntu 13.10
Package: login 1:4.1.5.1-1ubuntu6
ProcVersionSignature: Ubuntu 3.11.0-8.15-generic 3.11.1
Uname: Linux 3.11.0-8-generic x86_64
ApportVersion: 2.12.5-0ubuntu1
Architecture: amd64
Date: Sat Sep 28 20:44:17 2013
InstallationDate: Installed on 2013-09-27 (1 days ago)
InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Beta amd64 (20130925.1)
MarkForUpload: True
SourcePackage: shadow
UpgradeStatus: No upgrade log present (probably fresh install)
modified.conffile..etc.subgid: [modified]
modified.conffile..etc.subuid: [modified]
mtime.conffile..etc.subgid: 2013-09-27T12:14:50.513441
mtime.conffile..etc.subuid: 2013-09-27T12:14:50.389441