Try using an fdisk-type tool to change the partition type code. I'm most familiar with Linux fdisk, so I'll describe it in more detail:

1. If necessary, download a Linux emergency system, such as PartedMagic, boot it, and get to a command prompt.
2. Type "fdisk /dev/sda" to open fdisk on your disk. (You may need to change the device name to /dev/sdb, /dev/sdc, etc.; or possibly /dev/hda, /dev/hdb, or something in that line.)
3. Type "p" to view your partition table and verify it's the right one based on the number of partitions, reported disk size, etc.
4. You'll see the partition type codes in the "Id" column. For Windows, these should probably be "7" (0x07); for OS X, it should be "af"; for Linux, "83"; and so on. (Type "L" to see the codes known to your version of fdisk.)
5. If a partition has the wrong type code, type "t" to correct it. The program will ask for a partition number and type code. Enter them.
6. Verify your changes by typing "p" again.
7. Save your changes by typing "w". The program will write the changes to disk and exit. (If the type codes were OK and you didn't make any changes, then type "q" here instead of "w".)
8. Reboot.

If I'm right, this procedure should fix your problem. If it doesn't, then something other than the type code is causing Chameleon to misidentify your Leopard partition. The only other idea I've got is that the partition might have been damaged by Parted. If so, then fixing it in OS X's Disk Utility might fix the problem.