var $Prefs = {
	_getBranch : Components.classes["@mozilla.org/preferences-service;1"].getService(Components.interfaces.nsIPrefBranch),
	_getService : Components.classes["@mozilla.org/preferences-service;1"].getService(Components.interfaces.nsIPrefService),
		
	set : function(pref_name, pref_value) {
		var str = Components.classes["@mozilla.org/supports-string;1"].createInstance(Components.interfaces.nsISupportsString);
		str.data = pref_value.replace(/^\s*|\s*$/g,'');
		(this._getBranch).setComplexValue(pref_name, Components.interfaces.nsISupportsString, str);
	},
	
	get : function(pref_name){
		try{
			return (this._getBranch).getComplexValue(pref_name,Components.interfaces.nsISupportsString).data;
		}
		catch(e){ return false;}
	},

	remove : function(pref_name){
		try{
			(this._getBranch).clearUserPref(pref_name)
		}
		catch(e){}
	},
		
	remove_all : function(pref_name){
		try{
			(this._getBranch).deleteBranch(pref_name,'')
		}
		catch(e){}
	},
			
	branch : function(pref_name){
		var serialBranch = (this._getService).getBranch(pref_name+'.');
		return serialBranch.getChildList("",{});
	}
}