If you remember I discussed on 29th August that I am planning to post How to integrate E-Business Suite with 10g Application Server ? In order to do same you need to first Install 10g Application Server on same or separate machine as you can't upgrade E-Business Suite Application Server i.e. iAS 220.127.116.11.2 . If you want to know your HTTP Server version ; check here how to check vesrion Click Here
So first step in integrating 10g Application Server with Oracle Applications 11i is to install 10g Application Server and to learn how to install 10g Application Server click on my post on 10 g Application Server i.e. Installing 10g Application ServerOn this post you will find Installation documents for 10g Application and overview of order of Installation.
Why should you as Apps DBA configure 10g Application Server from iAS 10222 ? 1. If you want to use Portal , earlier version of portal i.e. 18.104.22.168.4 which used to shipped with 11i is now desupported 2. Discoverer 4i is soon going to be desupported over this year & new one is 10g Discoverer 3. You want to use Single sign On feature with 11i 4. For better user management & Identity management .
So In order to prepare your self with 10g Application Server Integration go to my other post & try Installing standalone 10g Application Server of type Portal & Wireless.