Source tracking using SMTP API


In the documentation page How to setup email tracking, it says, "HubSpot will automatically add the following source tags to any link within your email to ensure any traffic generated from a link within your email has the correct traffic source attribution:

utm_content=[email ID number]
utm_campaign=[campaign name]
For transactional emails sent through the SMTP API, I’m seeing that utm_medium and utm_source appear in the enhanced links, but not utm_campaign. (I’m not concerned with utm_content.) The SMTP tokens are set up with a campaign name though, so this information should be available to Hubspot. I’m not sure what’s going wrong. Did I miss something in configuration?