Need help with scraping .net (ajax) pages

hi guys
I building a PHP based scraper for a local search engine. Recently many .net websites are using ajax (_dopostback) to navigate through the content without a query submission:
javascript:_dopostback('content','page#')
Also there are hidden values that can be extracted __EVENTTARGET, __EVENTARGUMENT & __VIEWSTATE
I have tried to post them with cURL but I failed. I can only get the first page contents, but not all or move next. Any help or ideas are appreciated.