25 year mortgage at age 55

itsfrommark

Hi!
Background
I have a 3 year fixed mortgage with Nationwide (expires June 2011) at a rate of 5.75%. I have a 25 year mortgage at age 55 which I have arranged to keep the repayments as low as possible until I pay it off at 65 with a pension lump sum.

Question
Are there any mortgages on offer which would permit a 20-25 year term at my age at a lower rate of 3.7% with fees of £1000 or less. This is because I would be better off ditching the fixed rate according to Martin's Mortgage Calculator. I cannot find anything suitable as yet - do any of the Mortgage Advisors on this forum have any comments please?

PS LTV - the property is worth £380,000 and I owe £80,000

thanks Mark