He's got it in his mind to be with you. You have him programmed right now (not intentionally mind you) that all good things are on the other side.

From now on, ignore him when you are on the opposite side of the fence. Start speaking to him only when you are on the same side of the fence. He'll stop the urge to dig since you are with him (his initial want to begin with). Don't even acknowledge him even in passing. Be consistant with this, as this will make all the difference.

As owners we have this tendency to give our pets mixed signals. Not intentionally, just out mis-understandings or lack of pack dynamics. EXAMPLE:

We want our pets to greet us with open arms. So when we come home and the dog jumps on us, we tend to say GOOD BOY, HOW YOU DOING. The whole time the dog is wagging his tail to no end. After greeting us, our company comes inside behind us (the dog has already been praised for jumping on us, so he thinks it's okay to jump on company) and the dog gives them the same greeting. We as owners naturally, in a stern voice or even yell at the dogs NO! DOWN! BAD BOY!!.

The dog has just received mixed signals. 1st it's okay, then he's turned into a bad boy.

Same thing with getting on furniture. If you think that you will not want them on them when they are older and bigger, don't allow them on them when they are younger and smaller.