You might perhaps want to write to either Phil Wheatley (Director General) and/or Michael Spurr who is Chief Operating Officer of the National Offender Management Service as detailed at
www.hmprisonservice.gov.uk/assets/documents/100048D9noms_org_chart_oct_09.pdf I believe their email addresses should be phil.wheatley@noms.gsi.gov.uk and michael.spurr@noms.gsi.gov.uk
You might also refer them to paragraphs 7.26 to 7.31 of Sir David Varney's report on transforming government services at
www.hm-treasury.gov.uk/d/pbr06_varney_review.pdf and paragraphs 3.51 to 3.67 of the Central Office of Information's Contact Better Practice Guide For Government Contact Centres at
www.coi.gov.uk/documents/gcc-third-edition.pdf Both these guides indicate that the cost of accessing government services on the telephone (especially for the country's least well off citizens) should be a major consideration for government departments and agencies in their choice of phone numbers. You then need to also mention the the fact that by using 0845 numbers they are charging 20 times as much per minute for anyone who needs to call a prisoner from a BT Payphone (20p per minute instead of 1p per minute) as an 01,02 or 03 number costs to call and that calls to them on 0845 numbers are excluded from fixed price bundled minutes packages on some landline packages and nearly all mobile phone inclusive minutes packages. This all seems to go against the advice of the COI and Sir David Varney about needing to consider the affordability of the cost of calls for the most economically disadvantaged members of society (which more often than not prisoners families tend to fall in to). You may also find this article about the cost of calling 0845 numbers on the Lancashire Council Trading Standards website at
www.tradingstandards.gov.uk/cgi-bin/lancashire/bus1item.cgi?file=*BADV650-1011.t... helpful. This clearly states "You should not use the terms 'local rate' or 'national rate', or any reference to local or national rates. You should also not use words which could imply a local or national rate (e.g. 'Lo-call', 'low rate', 'national call', 'standard rate')."
Given that prisoners are deprived of all other contact with the outside world other than phone calls and visits this does seem to be an especially important issue to resolve in prisons. But I expect it will be outside the control of the Governor of this prison, who will almost certainly not have been able to determine the phone number arrangements.
If you can't get anywhere I would suggest a possible visit your MP's surgery as even prisoners do still have rights (even though sadly and wrongly in my view they are deprived of the right to vote) and making the cost of these calls to prisoners unaffordable is about one of the most unacceptable examples of the misuse of 0845 numbers I can think of.
You might also perhaps want to bring this issue up with the Howard League For Penal Reform at
www.howardleague.org If recent dramatic coverage on BBC Radio 4's The Archers is correct it appears that prisoners may also be having to pay BT Payphone rates for their outgoing calls rather than residential rates and this can again hardly be acceptable given the 20 fold premium still charged on BT Payphones for calling 0845 and 0870 numbers.