I don't submit to DT or IS (don't have the time to fiddle around with them), but SS, BSP, TP, MSP, SPK, GS, FP, BWB (big white box) (can't recall the others) have accepted it with no problems.
I can send you a copy, but you'll need to send me your email address because I'd rather not post it in the forums. (go here:
http://photographyofgrace.com and click on the contact button and email me from there - I don't want to post my email in a forum either. Spam bots grab that like it was fish bait

)
When I join a new site I check their policy for model releases and usually send an email to support asking if my personal business release would be acceptable and so far it has been.
Some of the larger agencies may insist on their own, but most of the others post model releases for use. It's just a pain to carry around five or six different releases and have someone sign them all.
If DT and IS want their own, then you should compare their releases and create one with a blank space where the agency name goes. Then you have the blank signed, photocopy it and fill in the agency name.
I don't do nudes so I don't have a place on mine for identification, but if you do nudes you'll need a place where you can place a copy of the person's ID (I believe they need a photo ID these days) showing the person is of appropriate age for nude modelling.
One of the things I do for my own business is include on each release the image name and a thumnail size copy of the image so it's very clear what image the release is for.
EDIT: okay, how stupid is that? I can email you from the forum...too early in the morning.