Simplenews newsletter producing undecoded base64 email I have a client site that's running Simplenews with Mime Mail and SMTP Authentication Support. Everything works fine except when my client wants to include a link to a YouTube video (and just to be clear, this just a link to the video, not an attempt to embed a video in the newsletter). Here is an excerpt of the resulting newsletter email:


  PCFET0NUWVBFIGh0bWwgUFVCTElDICItLy9XM0MvL0RURCBIVE1MIDQuMCBUcmFuc2l0aW9uYWwvL0VOIiAiaHR0cDovL3d3dy53My5vcmcvVFIvUkVDLWh0bWw0MC9sb29zZS5kdGQiPgo8aHRtbD4KPGhlYWQ+PG1ldGEgaHR0cC1lcXVpdj0iQ29udGVudC1UeXBlIiBjb250ZW50PSJ0ZXh0L2h0bWw7nIGNoYXJzZXQ9dXRmLTgiPjwvaGVhZD4KPGJvZHkgaWQ9Im1pbWVtYWlsLWJvZHkiIHN0eWxlPSJi 


. . . and so on. No other links cause this to occur. When I look at the email source, the plain text version is fine. This only happens to the HTML version. I am thoroughly stumped. Has anyone seen anything like this?
It turns out this was a bug in the SMTP Authentication Module. It uses uses 8bit encoding in the Content-Transfer-Encoding header for the base64 encoded body. I applied this patch with success:

https://www.drupal.org/node/1741082#comment-9121815