Alexandro, I assume you want the 12V for the relay ? Sorry,
I've a ****load of mails to get through and haven't read all of
those in this thread

Consider my solution at

http://www.piclist.com/techref/io/relays.htm

(just before 1/2 way down the page)

for energising a relay at its nominal voltage and keeping
it closed with a holding voltage, which can be 50% of the
energising voltage. The energising/holding ratio will differ
from relay to relay so I can't promise success with yours

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