I'm using handcent right now and have never gotten this problem. But that def, looks like a handcent icon. Is privacy turned on in the notifications setting?
i'm having this same problem. It just started this morning. I've had handcent for months. Did you ever resolve this? Or anybody got a fix?Funny, I just registered to post this exact same question!! I too am running Handcent and have been getting the double notifications. I've turned off default notifications, have no other messaging applications installed. I even emailed various messaging app developers asking if it's coming from their program, and they've all said no. It's driving me nuts, I can't figure out where it's coming from!!
I took a screenshot, hopefully I can attach it here so you can see. Same white envelope. Always says "You have an unread message", even after I click on it. Only way to get rid of it is by pressing "Clear".
Maybe it's a Handcent issue? I emailed the developer, no response.