How do I enable Java on my new Iphone 5

Sally ~ Welcome to the Support Communities. When viewing your post, at right you'll see a More Like This section — the answer is there, i.e. the iPhone does not support Java. You can also search the Communities — see this tutorial:

ASC — Search the community

Java which is different to Javascript, is not supported on iPhone.

You can however look in the App Store for 3rd party Browsers that offer support for it.

For Javascript which agian is completely different to Java you can go to Settings->Safari, and Make sure its turned on there.