@Josh Absolutely correct. I meant since this involves a lot of things (a couple of them are listed by Markus on the ticket itself) to do, they can use a helping hand from a student developing full-time.
It's just a suggestion of mine, they are doing an incredible job and it's totally their call (they can mentor the project as well since they have already come so far with the ticket). :)
This project can be thought more of getting "Django indexes into Spartan mode" than just "extending expressions into indexes" as I had called it earlier, as it would power Django to do much more with indexes via class based indexes. So if it looks good to the community this can be included in the ideas page of Django's GSoC page.