no email text only email header in my zoho account

no email text only email header in my zoho account

Problem.
In my Windows Phone 8 (Samsung Ativ S) I got twice email in my Zoho inbox with only all header information (normally hidden) in view, but no message text. I can see this text only when I log in on my laptop to read this email in Thunderbird. The header information is then hidden of course.

All account setting, and the IMAP en SLL settings of my Zoho account on the Samsung Ativ S are correct. Windows Phone configures it automatically. But I checked, and I checked once more.

With other email accounts (also IMAP and SSL) there is no problem in the Windows Phone app. (I use the built-in e-mail app of WP)

Question.
Is there anyone who has any idea how this is possible and what to do about it?