basically all of them allow adult sites if you use a gateway page in-between... since text links pull better than banners anyway I use text to link to the gateway page which consists of a table with 2 colums: casino and poker, each with 1 half page ad and the rest 120x60 buttons with the site names.
I found these affiliate programs to be the best, especially in terms of support and stats:
http://www.integritycasinos.com/defa...f=100focb1-2-1
http://www.referback.com/index.asp?s=aff91582
http://www.incomeaccess.com/processi...g=a_4785b_2403