i had got a missed call from +237 once i think .. it was 2am at night and i was talking to gf . she had call from same no after few mins .. she got scared and asked me to call and check :S ..
i called back and some girl picked who was talking in hindi :O , she said i have won something blah blah and wanted my address , i said dont want still she kept asking . i cut the phone in little more than a min .
after that my balance got deducted by 200 bucks :O :O

. i called idea CC to ask since no international call is that much , they said its number from some server and charged 100 per min :| ..
so never call any such number i think mobile operators are also involved in these scams to get more money .