Apple Logic Pro /LogicExpress Discussion

I think that the answer to this will be no.....

Is it possible to alter the speed of a pre-recorded vocal track. I am  
wanting to slow a piece down by a couple of measures, without re- 
recording the vocals. Does anyone know whether this can be done  
effectively? It doesn't matter if the pitch drops as a result, I can  
easily change the backing track.

thanks in advance

Andy B