when others link to a post it does not show as trackback in my blog

my blog is using librio 1.0 wordpress theme. i see the incoming links in the admin panel. but the links does not showup as trackback link or pingback link in the respective posts in my blog (when others link to particular post in my blog).

how to make wordpress show trackback or pingback links in the comments section.

it used to work but after i started using librio theme with wp-spam-free it stopped showing links in the respective post comments.

anybody know how to solve this problem?