Hi, I'm new here

I registered because i bought an HTC hero on ebay (as-is). Initially I was planning on using it as a dev device. After using it for a while, I've grown to like it.

Is there any way that I can activate it with an actual phone company, (Right now I'm using Sipdroid + google voice to make calls over wifi)

or is a bad ESN a death sentence for the phone?