wrote:
Hi All,

Long time no post!

I am considering moving my Nokia 5140 across from Orange to o2, but
don't know much about the process.

There is a little man on the local market who does unlocking for £10
which seems reasonable.

Try this site.

http://unlock.nokiafree.org/5140

What is involved here?

Does the phone get flashed?

Shouldn't do.

Will I loose all my numbers? If so, can I use the Nokia utility to
backup before the flash and restore after. If so I will have to go
cable shopping.

Your numbers are most unlikely to get loose. You might lose them but I
think that's unlikely too. Always wise to back up though and you can always
use a pencil & paper.

Tim