I have tried a T-mobile sim.  O2 said I had a faulty hand-set, so I'm on
the train now heading to London, where the O2 shop at Euston has another
V600 waiting for me.  Trouble is, I have also tried another O2 sim, and
that worked fine.  Still, I'll try the other V600 and see what happens.
Pete.

Nope, I bought it from an O2 shop and the sim is an O2 sim, so I would have
been amazed if they were so dim as to sell me a phone that was locked to
another network.  The phone even comes on and displays the O2 animation
(bubbles rising through very blue water) so that I think it has been through
some sort of O2 filter.
I have also tried another pay-as-you-go O2 sim in the phone since posting
this originally, and that worked fine.
Still just get 'Insert SIM' with my own though.
I'm going to call in at the O2 shop on Euston station this morning and see
if
my SIM will work on the new V600 they have waiting for me.

I was impressed with the efforts that the O2 shops went to in order to help
(bought the phone in the Trafford Centre in Manchester, called them, they
arranged for the V600 to be at a shop that I could reach without too much
trouble) whereas Michelle and her team leader Brendan on the O2 member
services number  0870 444 3333 were blunt and wrong.  Without listening
for long they just told me I definitely had a faulty hand-set and that I had
to
go back to the shop where I bought the thing and get them to either unlock
it
or exchange it.  When I said that wasn't very helpful, Brendan said they
were
not even part of the same company.  Brilliant, and rather typically British
in
customer 'service'.  Any jobs going in America for middleware consultants?

Winge moan, not very English of me, my appologies.  I'll post again when (?)
the problem is sorted out.

Pete.