A quick and dirty solution that I use:
1. Add two instances of the hair.
2. Delete the cap from one and the tail from the other with the geometry editor.
3. Do similarly on the joint editor deleting the unnecesary bones from each hair.
4. Still on the joint editor, move the tail's figure's origin to the root of the tail
5. Place it properly and parent the tail to the other instance's head.
It is a bit cumbersome, but does the job for me. I'm not very skilled, so there might be better ways I don't know about. Here is a sample with OOT's Linda ponytail:
OOT Linda ponytail sideways
EDIT: Instructions improved