It's simpler to use a gate effect, I'm pretty sure that's what they did in the song... you just put it on the vocal track and it makes it stutter. Here are a ton of gate VSTs you can use:
http://www.kvraudio.com/get.php?mode...ts&st=f&q=gate I haven't tried any except CamelSpace though but I know it works well.. but any free VST should do the job just fine
P.S. That's also how you do the JT's "My Love" stuttering synth trick
