Contact Issues After Switching to WP8 from iOS

Hey guys,

I posted a topic last week about this issue I've been having, but it didn't get much traction in the Mobile forum. It was suggested that I post it in the Apple forum, but since it involves switching FROM iOS to WP8, I thought I'd try it here.

I purchased a Lumia 928 a week or so ago and came to realize that some of my friends and family members who still have iPhones could not send text messages to me anymore. They would get error messages or the text would just not go through. My thinking is that this has something to do with iMessage.

I took my already hard reset iPhone and set it up again and turned on iMessage. I waited a couple of days for activation, but nothing ever happened. I hit the "OFF" switch for iMessage, hard reset the phone again, and turned it off. I'm still getting friends that say their text messages aren't coming through.

I thought that maybe changing me in their contacts from iPhone to Mobile would help. Well, one guy having trouble already had me as mobile. I deleted my contact from his phone, re-added it, and then it worked.

With all of that being said. Do any of you have experience with this? I'd like a fix for this issue that wouldn't require anything out of the people trying to contact me. I was really hoping turning off iMessage would do the trick, but it didn't seem to work for everyone.

Thanks in advance for your help!