Caller I.d

hi, pls i posted this in some other section and got blasted for it,
i need your help here.

hey pips am gonna need help,

am getting treat messages from some1 and i need to know who.

the person calls my mtn, and uses a restrained caller i.d,

is there a way i can findout the callr.

i know u have to work with one of this mobile coys to have such access, but i wud love to knwo. tanx.