Thunderbird 0.7 :(

is out so I wanted to upgrade. I closed my running version of the product. copied the newly downloaded Thunderbird in my /Application folder and started the product, my profile was lost and a new created profile was created. I removed that new profile but 0.7 did not work better, so I trashed it. And did not even bounce ! And nothing got written into the system log so I could undertstand what was going on. (I should Have trashed 0.6 before upgrading I know, but still this is unpleasant). Going back to 0.6 got my profile recognised and my mails back. Will try later another upgrade.