In deed, I believe bug 1045944 should be marked as a duplicate of this bug.
I did a repeat test this AM with the most recent Lubuntu live image and there is no option to create a logical partition.
In fact using a blank 80 GB drive and creating /boot, /, /home, and swap I end up with all primary partitions.
Please see the attached screenshot.
In deed, I believe bug 1045944 should be marked as a duplicate of this bug.
I did a repeat test this AM with the most recent Lubuntu live image and there is no option to create a logical partition.
In fact using a blank 80 GB drive and creating /boot, /, /home, and swap I end up with all primary partitions.
Please see the attached screenshot.