UK Mobile VoIP numbers?

This question just in from a reader (oh alright, it’s my own question):

Can anyone recommend a company that can provide a few UK virtual mobile numbers with voice terminated over SIP and SMS over SMPP or some other API?

Preferably not numbers that are stupidly expensive to call and excluded from other MNO’s minutes buckets.

Let me know in the comments or via e-mail: dan.lane@mobileindustryreview.com