put something like this in your robots.txt file:

Code
User-agent: *
Allow: /
Sitemap: http://jakchat.com/sitemap.xml
Disallow: /files/texts
Disallow: /forums/ubbthreads.php?ubb=calendar
Disallow: /forums/ubbthreads.php/ubb/calendar
Disallow: /forums/ubbthreads.php?ubb=showday
Disallow: /forums/ubbthreads.php/ubb/showday
Disallow: /forums/ubbthreads.php?ubb=showprofile
Disallow: /forums/ubbthreads.php/ubb/showprofile
Disallow: /forums/ubbthreads.php?ubb=showmembers
Disallow: /forums/ubbthreads.php/ubb/showmembers
Disallow: /forums/ubbthreads.php?ubb=online
Disallow: /forums/ubbthreads.php/ubb/online
Disallow: /forums/ubbthreads.php?ubb=search
Disallow: /forums/ubbthreads.php/ubb/search
Disallow: /forums/ubbthreads.php?ubb=faq
Disallow: /forums/ubbthreads.php/ubb/faq
Disallow: /forums/ubbthreads.php?ubb=viewprivacy
Disallow: /forums/ubbthreads.php/ubb/viewprivacy
Disallow: /forums/ubbthreads.php?ubb=mycookies
Disallow: /forums/ubbthreads.php/ubb/mycookies
Disallow: /forums/ubbthreads.php?ubb=markallread
Disallow: /forums/ubbthreads.php/ubb/markallread
Disallow: /forums/ubbthreads.php?ubb=newuser
Disallow: /forums/ubbthreads.php/ubb/newuser

this will stop search engines from indexing unnecessary pages.

JakChat.com -- Forums for Indonesia's English-speaking community
Ubuntu-Indonesia.com -- Forums for Indonesia's Ubuntu Users