A question about Forum Public Profile Page pagerank

[sukantab]

Hi All,
I have a question, may be it is dumb, but I don't have an answer.
I am participating in 3-4 other domianing forums like DP, NP, WMT, Domainstate etc other than DNF.
I have seen that only at Digital point user's profile page is Pageranked.
If you have good number of posts and you frequently keep posting you will get a pageranked public profile page. (To see yours, go to one of your forum posts, click on your user id and click public profile).
With 800+ posts, I have a PR2 profile page at DP...
But in no other forum, I could see anyone having a pageranked public profile page.
I have checked for the user ids with at least 3000+ posts in all other forums including DNF, but could not find one.
Any idea of how this is done?

Thanks...

 

[rusty123]

I was going to say they probably have robot.txt or nofollow blocking spiders from profile pages so they dont get indexed and pagerank. But i see a couple of dnforum profiles are indexed. Perhaps DP have more backlinks to there profile pages.