@Cunedda Just to add another point to softech's advice, I found that 011 plus country code didn't work for long distance calling a little while ago even for saved numbers that I had no problem calling before and I had to instead replace the 011 with + 44 (or whatever country code) before my call would complete.
Not sure if this was a problem for a short period or something has changed, but it might be worth trying in case you're still experiencing problems calling the UK number.
On a side note, also noticed for some really strange reason that my uninterrupted international call deducted from two different international add-ons (luckily both gifted) which I found really odd, but then, again, this is PM which has a lot of idiosyncrasies all over the place..
