Yes, we should investigate all the possibilities.
In case I'm not responding in time to the captcha MMS, the next try should be sent to my aunt Rema who has more time. The only problem is that she doesn't have a computer. She would then call my little niece Irma who would then send the e-mail to my account.
An alternative for e-mail would be to use the remote interface to jD, but extended with captcha responses.
Wouldn't the easiest solution for such customers be to run jD on their smartphone? Most smartphones support Java. Communication would be a little expensive, but for small files this wouldn't be an obstacle I suppose. This would be a really 'portable' solution for jD.