Well, it is partition sdb15 in Linux parlance, so maybe the message is just saying which partition.
First, I created it as type a504 (FreeBSD ZFS). The Handbook says it doesn't matter, as it will change it anyway. When a504 didn't work, I tried 8300 (standard Linux data). The error message was the same.
My two SATA III drives total 3 TB. They are both GPT partitioned, and they have quite a few GPT partitions on them. There are no extended partitions of any kind. My gdisk program is version 0.8.10-1 from the Debian unstable repository.
Here is the current partition info for that drive:
Disk /dev/sdb: 3907029168 sectors, 1.8 TiB
Logical sector size: 512 bytes
Disk identifier (GUID): 057E767D-1AA6-4E96-A940-B540B5580A82
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 3907029134
Partitions will be aligned on 2048-sector boundaries
Total free space is 3407902829 sectors (1.6 TiB)
Number Start (sector) End (sector) Size Code Name
1 2048 6143 2.0 MiB EF02 BIOS boot partition
2 6144 62920703 30.0 GiB 8300 Linux filesystem
3 1954551808 1971329023 8.0 GiB 8200 Linux swap
10 62920704 188749823 60.0 GiB 0700
11 2218817536 2260760575 20.0 GiB 8300 Linux filesystem
12 2260760576 2323675135 30.0 GiB 8300 Linux filesystem
13 2323675136 2355132415 15.0 GiB 8300 Linux filesystem
14 2355132416 2397075455 20.0 GiB 8300 Linux filesystem
15 188749824 304093183 55.0 GiB 8300 Linux filesystem
Tim