When searching for an email address, the comparison if a user has a viewable email address is returning wrong results if the user displays both of his addresses (line 88). A short circuit is the Wrong Thing in this case.
I attach a small patch for this, as I don't have a Goathack account yet (I'm waiting for it...).
Update: Okay, so this wasn't it. Too quick to fire at the wrong target. But the bug is there: the search through multisearch.bml chokes on some addresses, like