When I'm going for screechy sounds like that, generally I start with saws, add some hardsync, granular/waveshaping/bitcrush type effects. You basically just want to mangle the sound using a distortive effect, detune it heavily etc. and of course the reverb and compression.
I threw this one together in Zebra2 pretty quickly.. Using 2 oscillators in 11 mode (so 22 altogether..sort of) with heavy unison... I used an effect called Fractalz and Scatter (although they are not a requirement they just help granulize it a little). Then of course add the requisite portamento effect as has already been pointed out. It's not exactly the same but with a little work it could be made to sound almost identical. I don't have a virus at the moment to whip up a patch you can use, but the basics are pretty much the same on any subtractive synth.
Here's my fast and dirty imitation:
http://www.mediafire.com/?mi40z8dih7pug3b