If you don’t like JomSocial’s default wall application you can go to the download section on Compojoom and download the plugin “compojoomWalls”, then install it trough Extensions->install/uninstall . After that don’t forget to enable that plugin and choose if you wish to globally enable it, or let the user decide if he/she wants this application.
Now what you still have to do is to go to: components->CompojoomComment->settings and click on new. From the component dropdown list select com_community and click save. Now you should see the CompojoomComment in your profile.