Trackbacks, Pings and Custom Fields

Does anyone use custom fields to hold references to other posts?

I having a problem trying to get trackbacks showing up when a URL is pulled from a custom field into a post.

Right now this is how it’s set up:

Post 1 is written with a url of, e.g. https://sample.com/archive/1

Then Post 2 is written and adds a custom field with a value of https://sample.com/archive/1 .. this Post 2 pulls the info from the custom field (via the single.php template) and displays it in the post.

Theoretically, it seems as though Post 1 should now show Post 2 as a ping/trackback. However, this isn’t working. The only way to get Post 1 to show Post 2 as a ping/trackback seems to be by putting a link to Post 1 right in the body text.

Anyone run into this before?

Thanks!