Question : Problem: What is a telephony connector j9d1

I am just reading over my motherboard manual of my Dell Dimension 4700 series desktop computer and noticed there is a connector for a telephony connector (j9d1) could someone tell me what this connection is for and where I could find out more information about it?

Answer : Problem: What is a telephony connector j9d1

it connects to an isdn line
more info on the 4700 pages : http://support.euro.dell.com/support/topics/topic.aspx/emea/shared/support/root/en/product_support_central?~ck=ln&c=uk&l=en&lnki=0&s=gen

or tryto contact Dell for it : http://support.euro.dell.com/support/topics/topic.aspx/emea/shared/support/dellcare/en/contact_us?~ck=ln&c=uk&l=en&lnki=0&s=gen