BB Torch :: Mobile Phone Icon For Contact Showing Up In SMS

When one of my phone contacts texts me, their name has a small mobile phone icon at the side of their name instead of the standard icon.This icon also shows up in my email inbox and BBM when they text me, and I can also open their texts in my email and BBM.I can also reply via SMS using my email and my BBM.When they text me a message, the standard message symbol doesn't appear, although the light flashes the colour I have set to that contact, and a BBM symbol comes up. If I open the message in the SMS or Email inbox, the BBM symbol disappears. I've tried rebooting the phone, and it doesn't do this with any other of my contacts.