from http://members.optusnet.com.au/cjbarton/BPY_API/Ipo-module.html

current:

from Blender import Ipo

ob = Ipo.Get('ObIpo')          # retrieves an Ipo object
ob.name = 'ipo1'                                 # change the Ipo's name
icu = ipo[Ipo.OB_LOCX]         # request X Location Ipo curve object
if icu != None and len(icu.bezierPoints) > 0: # if curve exists and has BezTriple points
	val = icu[2.5]              # get the curve's value at time 2.5
	icu[Ipo.OB_LOCX] = None     # delete the ipo curve

should be:

from Blender import Ipo

ob = Ipo.Get('ObIpo')          # retrieves an Ipo object
ob.name = 'ipo1'                                 # change the Ipo's name
icu = ob[Ipo.OB_LOCX]         # change here ipo to ob
if icu != None and len(icu.bezierPoints) > 0: # if curve exists and has BezTriple points
	val = icu[2.5]              # get the curve's value at time 2.5
	ob[Ipo.OB_LOCX] = None     # change here icu  to ob