Import vCard with Photo URLs (not embedded)

I’m trying to import vCards that use URLs for photos instead of embedding them in the vCard, but everything I have tried results in the contact being disregarded.

For example:
PHOTO;TYPE=JPEG:http://example.com/photo.jpg
PHOTO;JPEG:http://example.com/photo.jpg

Is this an unsupported option, or am I doing something wrong?