pingback problem

now here’s an interesting one…
I posted in my ‘main’ blog, and included a link to my other blog. Not a link to any specific post mind – just to /wordpress/
I now have a pingback on the very first entry. Not really a problem, as I can easily delete it, but I’d hate to ‘pingback spam’ someone else in this way.
I’ve linked my other blog before, but it’s never sent a pingback before. Only thing I’ve changed since last time is upgrading to 1.2.1 (from 1.2)
I’m sure I’ve read about this problem before on here a while ago, but I searched and couldn’t find anything 🙁 Can this be fixed?