Would ANYONE have the slightest idea why I would not be able to receive MMS from former Alltel users still using Alltel phones?

I get them from my friends on Verizon, T-Mobile, whatever..
My mom, my brother, and my other friend all use phones that have Alltel branding...I've tried multiple times to send MMS to my phone from theirs, to no avail.

They receive my MMS, but I don't receive theirs... I remember being able to back when I first got my new phone line on Verizon. I used to have an old Alltel number, and a Samsung Delve and I received MMS just fine.

When I got my Storm I received MMS from everyone, for about 2 weeks, and then it just stopped.

SO to reiterate, I don't get MMS messages from Alltel phone users, but from everyone else.
Ideas? Solutions? I brought this up to a sales rep in the store one day and he spent over an hour on the phone with Tech. Support and they still couldn't figure it out.

 

Yes it is, it seems I can't get MMS from anyone who was using Alltel before the merger.

 

Well hello.
I tried using Handcent, and the native app. I sent a pic to my mother's phone, and back to mine from hers. I didn't get it back.

 

Well an MMS without pics is an SMS lol
It accepted them before we got switched to Verizon.. I don't get it.
It pretty much stopped working after I got a Verizon branded phone..