Oops.. you should have used 'Disk Druid' - it makes it
much easier to create multiple extended partitions.
Extended partitions are just parts of your last partition,
e.g. here there are only two primary partitions, /dev/hda1
(which is very small, for /boot) and /dev/hda2 which is
the rest of 4GB drive partitioned in smaller pieces.
root@klingon 14:16:56
/root>$ fdisk -l
Disk /dev/hda: 255 heads, 63 sectors, 524 cylinders
Units = cylinders of 16065 * 512 bytes
Device Boot Begin Start End Blocks Id System
/dev/hda1 1 1 4 32098+ 83 Linux native
/dev/hda2 5 5 524 4176900 5 Extended
/dev/hda5 5 5 196 1542208+ 83 Linux native
/dev/hda6 197 197 324 1028128+ 83 Linux native
/dev/hda7 325 325 347 184716 83 Linux native
/dev/hda8 348 348 367 160618+ 83 Linux native
/dev/hda9 368 368 383 128488+ 82 Linux swap
/dev/hda10 384 384 524 1132551 83 Linux native