Access to sharepoint sites via subdomains

[dds]

Hi, everybody!

I can't solve one problem for a long time.

There is a sharepoint portal on domain.com, which has sites

domain.ru/site1
domain.ru/site2

etc.

I need to access sites via subdomains, e.g.
site1.domain.ru should show the domain.ru/site1 content. But it's necessary to show URL site1.domain.ru in browser's address bar.

I tried to solve it with ISAPI_Rewrite, then with ISA Server as reverse proxy, and alternate access mappings in sharepoint.

But unsuccessfully. Any one faced this or similar problem?

[dds]

Ok, I managed to config redirection. But now, when I go to site1.domain.com, I see a blank page with URL
domain.com/_layouts/spsredirect.aspx?oldUrl=http%3A%2F%2Fdomain.com%2Fsite1%2FPages%2FHome.aspx
Why the redirection is not working?