Zimbra mobile : page contains both secure and nonsecure

[g00_t]

I am receive the message "This page contains both secure and nonsecure items." when browsing some messages from mobile interface using IE6.

It doesn't occur using Firefox or IE 8. I used the full browsers to troubleshoot because I could not browse the messages from a mobile device.

I have tried WM6 and two BB 8820 's. The mobiles do not display an error message, but the email isn't fully displayed. Only From, to and subject is displayed.

any idears?