Apparently it was an option ( the only option) so may not have been fitted,but it seems the reclining seats are part of it so if you have not got these you won't have the massage function either, perhaps a trip to Lexus would confirm.
Taken from the AA review in 2007
"The car's only cost option pampers in the extreme, boasting electric reclining seats, thigh and leg support for the left-hand chair plus a massage function. Separate DVD player and climate control operation is contained in a fixed centre console"