(Note that VSP and IVT use different evacuation packages.)
G. Lämmel, TU Berlin
http://www.matsim.org/javadoc/org/matsim/evacuation/package-summary.html
http://www.matsim.org/javadoc/org/matsim/evacuation/package-summary.html#evacuation_parameters
I (kn) can't say how this works. There is, at this point, neither documentation nor funding.