Meetme Conference in Trixbox

Hi All,
I am a trixbox user. Does anyone know where I can change the tone which is played when a new user enters a conference?
Right know the user recods his/her name and when entering the conference attendies hear

Entry Tone “(Recoreded user name) is now entering the conference” Tone.

I would like to change the last tone to something else???

Thanks,
Chris