Problem with some Radio 3 programmes.

[Budge]

I have found that The Early Music Show appears in my cache but when I
try and download using the cache reference I get the following message:-

alastair at X3400:~> get_iplayer --get 12899 --type=radio
get_iplayer v2.91, Copyright (C) 2008-2010 Phil Lewis
  This program comes with ABSOLUTELY NO WARRANTY; for details use
--warranty.
  This is free software, and you are welcome to redistribute it under
certain
  conditions; use --conditions for details.

Matches:
12899:  The Early Music Show: Valentine's Music - Love Is a
Many-Splendored Thing, BBC Radio 3,

INFO: 1 Matching Programmes
WARNING: No programme versions found
alastair at X3400:~>

This does not happen with other Radio 3 programmes in the cache, for
example CD Review. 
What is happening here and how should I overcome this problem?