There is a "code" at the top of messages I send that is distracting

When I create a newsletter I get line at the very top that looks like this:

/* 272740-1381459332-ai */ /* 272740-1381459332-ai */

I assume that this is some kind of a tracking code?

here's the web view of it:

http://www.caledonia.net/?view_newsletter=1&view_newsletter_code=1381461497&view_newsletter_send_id=1381462528

Is this normal?

Thanks.

Danita