Ok, I've looked a little bit more at things, and maybe I've confused things by interpreting what I've seen listed...

The '02 Murrays catalog shows the spinnaker kits by Hobie with the following dimensions for the 20 chute:
luff - 27.58 leech - 25.0 foot - 17.0

Given the fun of laying out spins and measuring them, this is probably the sail you have. The most recent Hobie catalog I have shows the same part number as this kit.

The '03 Murrays catalog shows the Hobie spinnaker kits with the chute for the 20 being listed as Tiger/20, with the following dimensions:
luff - 27.56 leech - 24.33 foot - 12.0

Similar luff and leech, smaller foot. Depending on who you believe about spinnaker design, the higher aspect ratio design on the Tiger sail might be just as fast without the extra sail area.

But I guess my question now, is what is Hobie actually selling for the boat if you were to get a new one now that wasn't old stock? I'll have to dig a little more I guess...