If the animation is cycling and you want to change the animation time, pass in 0 for the animation number. Does that work for you?
Code:
import viz
import vizact
viz.go()
avatar = viz.addAvatar('vcc_male2.cfg',pos=[0,0,5],euler=[180,0,0])
avatar.state(4)
vizact.onkeydown('1',avatar.setAnimationTime,0,5)
vizact.onkeydown('2',avatar.setAnimationTime,0,13)