if(existing instanceof CastableArray){
((CastableArray)existing).appendEL(value);
}
else if(existing instanceof String){
CastableArray ca=new CastableArray(existing);
ca.appendEL(existing);
ca.appendEL(value);
sct.setEL(key,ca);
}
else
sct.setEL(key,Caster.toString(value));