guys there is absolutely no need to panic on this.i hope u ve already figured it out but if not, let me explain.
you all know that steering wheel needs a constant supply of electric current to keep the horn alive.but u also know that steering wheel always remains in circular motion so no solid connections can be made with to to provide current.thats why they connect the steering piece with the steering coulmn ( for electric current) with a small metal strip which keeps on running on the metallic circular strip of the steering wheel. this way, the steering is always in connection with the electrical circuit for horn even if its being turned.
i made a pic to illustrate what im talking about here.

now the problem is that somehow the grece which keeps the two rubbing smoothly drys out sumhow, may be they dont use enough of it or may be they dont use it at all.so all u have to do is get it greaced and it ll be gone for ever.nothing to worry about.