mike wrote:

How come the Germans haven't joined in the "unified" colour coding then?

The have so far as flexible cord colours are concerned. TTBOMK that's
been fully harmonised since around 1970. Harmonisation of colours for
fixed wiring has taken much longer and until earlier this year the UK
was odd-man-out in allowing black for neutral. The situation now is
that all EU member states use blue for neutral and green/yellow for
protective earth. The colours for the three "live" phases varies, with
some states using three browns, some three blacks and some brown for L1
and two blacks for L2 and L3. Rather oddly Germany uses black, brown,
black for L1, L2, L3 respectively and thus black for the "live" in
single-phase installations.

One reason for the delay in the UK coming into line was that our
national standards committee wanted to preserve the use of three
distinct phase colours, so that the phase sequence was clear from the
wiring colours alone. As we all know they succeeded and BS 7671 now
requires brown, black, grey.

There's a summary of phase colours by country in this document:
http://www.iee.org/Publish/WireRegs/Impact_2004.pdf

--
Andy