How Do I Combine Microsoft Accounts?

Hey everyone,

I have a Microsoft account that I use for my Xbox Live Gold subscription and another Microsoft account that I use on my Windows Phone.

Now, I'd like to use the same account for both, and I'm having trouble finding the best way to go about it. I'd like to use my Windows Phone Microsoft account for my XBLG subscription.

Can any of you dudes or dudettes help me out?