It is more or less what I would expect is required,
but (because of arcgisscripting?) it devolves each point to its x and y components.
It seems to me that it would be simpler to just re-order the points in the line array
rather than to re-build them.
Replacing arcgisscripting with arcpy is the first upgrade I would suggest.
getPart ({index}) on the line object will
return an array of point objects for a particular part of geometry
(or an array containing a number of arrays, one for each part)
step through the array, and build a new, reversed array
get the point from the existing line object array using array.getObject (index)
then add it to the new array.
You can use newArray.insert (0, thePnt)
(to take the existing points in order and adding each to the beginning of the new array)
or
take the points in the reverse of the existing order (decrimenting the index to 0)
and adding them each to the end of new array with newArray.append (value).
Now use the new array to build a new polyline object
and update the feature in the table row.
Sorry, no code, but I think re-doing the script in arcpy is the first step:
there are some better tools in the newer module.