CentOS - Apr 2007 - Upgrade 4.4 to 5.0 (Error in transaction)

Hi!

I'm having a problem upgrading an existing 4.4 installation to 5.0. 

- The machine is a x86_64 architecture
- I'm upgrading from a DVD
  - I've used the same DVD to sucessfully upgrade another machine
    (therefor I'm pretty sure that it is OK)
  - The error occurs on both DVD-drives on the machine (therefor I
    think its not a problem with a particular DVD-drive)

I'm clicking through the upgrade dialogs. Then the machine prepares to
install the packages. At the end of this a dialog-box appears:

Error running transaction
There was an error running your transaction for the following
reason(s):

Apart from that text there is only a Reboot-button (no explanation)

On the other virtual terminals there is nothing unusual (last line in
Ctrl+Alt+F3 is "Preparing to install packages")

The /root/upgrade.log is empty.

My guess is that there might be some packages that offend the
installer (there are some non-standard packages on the machine, don't
shout at me: I know that's bad (amongst them a 32-bit firefox)). Is
there a way to find out which packages are the bad ones?

Any tips would be most welcome. Thanks

PS: What I'm trying right now is removing the worst offenders and retry
the upgrade procedure in text mode.

Just an update and an additional question concerning this:
>>>>> On Mon, 16 Apr 2007 19:53:34 +0200
>>>>> "bl" == bgschaid lists <bgschaid_lists at
ice-sf.at> wrote:
    bl> Hi!

    bl> I'm having a problem upgrading an existing 4.4 installation to
    bl> 5.0.

    bl> - The machine is a x86_64 architecture - I'm upgrading from a
    bl> DVD - I've used the same DVD to sucessfully upgrade another
    bl> machine (therefor I'm pretty sure that it is OK) - The error
    bl> occurs on both DVD-drives on the machine (therefor I think its
    bl> not a problem with a particular DVD-drive)

    bl> I'm clicking through the upgrade dialogs. Then the machine
    bl> prepares to install the packages. At the end of this a
    bl> dialog-box appears:

    bl> Error running transaction There was an error running your
    bl> transaction for the following reason(s):

    bl> Apart from that text there is only a Reboot-button (no
    bl> explanation)

    bl> On the other virtual terminals there is nothing unusual (last
    bl> line in Ctrl+Alt+F3 is "Preparing to install packages")

    bl> The /root/upgrade.log is empty.

    bl> My guess is that there might be some packages that offend the
    bl> installer (there are some non-standard packages on the
    bl> machine, don't shout at me: I know that's bad (amongst them a
    bl> 32-bit firefox)). Is there a way to find out which packages
    bl> are the bad ones?

    bl> Any tips would be most welcome. Thanks

    bl> PS: What I'm trying right now is removing the worst offenders
    bl> and retry the upgrade procedure in text mode.

Text modus doesn't help

Stupid question: is it possible that the reason for this error message
is that the estimated size of all the packages that are to be updated
(3.2 Gig) is bigger than the remaining free space on the root
partition (2.5 Gig)?