New install using GUI installer (used fdisk to write empty partition tables to disks before starting install) Using fdisk, I created partition tables on two drives, including a swap partition which I made type 0x82. anaconda then brought up disk druid to label the partitions, where the swap partition was correctly recognized as swap. I mkfs'ed and set mount points for all the 0x83 partitions, and did nothing with the swap partition. When I hit next, a warning popped up about no swap being available. I was only able to get it to recognize the correctly created swap partition by hitting back and changing the type of swap to ext3 and then back to swap. After doing that (which I shouldn't have had to do -- it's highly non-intuitive), the installer died with "a serious error initializing swap". I was finally only able to get install to proceed by starting over from scratch, creating swap in fdisk, telling anaconda to proceed without swap, and manually running mkswap, swapon, and adding an entry for swap to /etc/fstab after the install finished. The swap partition I created was 512 megs, which certainly isn't unreasonable. I have no idea why anaconda choked on it.
We have been discussion how to handle your original situation better. The issue arises because the GNU parted library we are using for partitioning now looks at the actual filesystem on the partition to determine its 'type'. This does not have to match the numeric partition type code stored in the partition table, which leads to the confusing situation you encountered. There wasn't really room in the main Disk Druid interface to show both the partition type and the filesystem type unfortunately. I am thinking about adding a dialog which pops up when you enter the Disk Druid screen to report when there is a mismatch of this type. That way the user will have a better understanding of the situation.
Very similar to bug 51349.
This defect is considered SHOULD-FIX for Fairfax.
This should be handled more sanely in RC1.