Why is my iPhone not sending any mms messages? - 1

I have an iPhone 3GS (I know it's an old phone). I have the prepaid pay as you go SIM card. I don't have data on it; all I have is unlimited messaging which includes mms messages. I put my SIM card in and I tested everything out. I sent messages, I called people, I connected to Wi-Fi and see if everything worked, and I also sent picture messages to see if it worked. It did. It worked perfectly fine. I could send and receive picture messages. But recently, it hasn't been working. I just updated to iOS 6 and I don't know if that has anything to do with it. I also have mms messages on in my settings. Every time I try to send a mms message, the send bar goes really slow and towards the end it stops. It will let me send mms messages on iMessage while I'm on Wi-Fi, but it won't let me send any to anyone that doesn't have iMessage, even when I'm on Wi-Fi. I have mms messaging on my plan. I don't know why it was working perfectly fine and then it stopped.

Can i swap my iphone 4 sim with an iphone 4s?

I have an iphone 4 now with sim card and a plan for it. Now if i buy a new iphone 4s will all i have to do is put the iphone 4 sim card in the 4s and everything will be fine? Will i have to talk to my service provider?

Why does my iPhone not stay connected to the internet?

My phone is in a constant state of logging on and off of the internet and will not stay connected. I have an iPhone 4, I just updated to iOS 6, I've sync'd to iTunes, restarted my phone, turned off Wi-Fi and turned it back on, and even reset my home internet but nothing has fixed the issue. I'm also unable to update my apps, but thats another question. Anyone know what could be wrong?

I have os x version 10.5.8 on my mac, but i need 10.6.8?

I'm trying to find version 10.6.0 but i can't find it anywhere. I need itunes 10.7 because i downloaded ios 6 for my iphone and now that won't sync because i need the version. So where can I get 10.6.0 for my mac for free

If I buy an unlocked Apple iPhone5 online in America will it work in Ireland?

I was wondering if I got my cousin in America to order an Apple iPhone 5 online from the Apple store & it was delivered to him in America, then shipped to me, would it be fully functional in Ireland? Because it says when you buy one online that they are unlocked? Reply As soon as possible, thanks!

Added (1). I would just be worried that the App Store wouldn't work? Also would I have to jailbreak the phone for it to work?