[Plugin: Custom Contact Forms] Data submission as text message error

I’m using Custom Contact Forms to send emails to my cell phone using this email 10digitsphonenumber@operator.com
I’m receiving messages with the following error:
“To view the message, please use an HTML compatible email viewer.”
I’m using Android 2.2.2 and I tried to send emails from Outlook and gmail using this email and it works.
So how can I change the form that I could view submission data as a plain text on my phone?

http://wordpress.org/extend/plugins/custom-contact-forms/