Description of problem: mail-notification stopped working after at-spi got updated some weeks ago; see Bug 227828 for details. Erik van Pienbroek (CCed) did analyze the problem in Bug 227828 Comment #6 and comes to the conclusion that at-spi is the culprit for the problem. I did take a look into it myself and currently think he's right. He uploaded a testcase to that bug to confirm the problem. Is his analyze correct? If not: do you have any hints how to fix mail-notification?
According to the discussion in Bug 227828 this is not a bug.