for all new sony's, including k800i, k810i, w850i, w950i, w880i etc there are 4 types of firmware, each firmware requires differing amounts of server codes to unlock. there server codes are expensive (ie. circa 4-5 pounds each, with some phones needing 6 codes
and thats me buying them 1000 at a time
)
the firmware's are CID49, CID50, CID51, CID52.
the 49, 50 and 51 firmware's are quite easy to unlock and only require 3, maximum 4 codes. CID52's need reflashing THEN 6 codes applying, adding to the already expensive unloking cost...
unfortunately 95% of w880i's are CID52's...
40.00 including labour to unlock
i strongly recommend a Sony W580i...same features as w880i, lovely little slide up phone, very tempted myself, circa 140 notes sim free.
can get them in black/gun metal grey etc