Can one "rollback" package updates?

[Matt England]

I should probably clarify:

Removing 1 package may not be difficult.   It's the broad set of packages 
that one can install (eg, via the "Software Updates" gui tool) that's more 
difficult.  It's hard, if not impossible, to know which packages

I don't want to have to do a system snapshot/backup at a low level (eg, dd 
or file-system snapshot); I'm hoping to track this at an OS/application level.

Also:  what happens after new package upgrades an old one, and the new 
package is removed?  Is the old package "put back" to its original state?

-Matt

At 5/11/2006 09:58 AM, Matt England wrote:
>I would like to be able to "rollback" package updates in the even that a 
>package (or a set of packages) causes new system-behavior problems after 
>installation.
>
>Is there a means to do this?
>
>Fyi, I'm a new Ubuntu user running Dapper Beta2 on a Thinkpad 2378DHU.
>
>-Matt
>