Custom Class Event Prototyping

programming flash
1

Ive been having a problem with a MovieClip prototype. The code i used is below - the problem being that the onLoad event never happens. Can anyone see an obvious problem? If i change the onLoad event to apply to the MovieClip class and not the PlaylistItem class then the event fires fine.

//constructor
PlaylistItem = function(){}

//inherit from MovieClip
PlaylistItem.prototype = new MovieClip();

PlayListItem.prototype.init = function(sInitTitle, sInitURL, iInitNum){
this.sTitle = sInitTitle;
this.sURL = sInitURL;
this.iNum = iInitNum;
this.sName = “track”+iInitNum;
}

//onLoad method
PlayListItem.prototype.onLoad = function(){
this._y = 20 * (this.iNum - 1);
}

//register class with library object
Object.registerClass(“playlistitem_mc”, PlaylistItem);

Thanks for any help with this - im at a brick wall if i cant understand why this doesnt work!
mafro