;)
In its quest to get you a good farm backup, SharePoint tries to pause it too during the backup. Unfortunately the UPS doesn’t pause, so the backup process actually un-provisions the UPS during the backup, undoing all your hard effort getting the damned thing to work in the first place. When the backup is finished it tries to put everything back together and it reprovisions the UPS. Now, what do we know about provisioning the UPS, besides the fact that it burns one of your three wishes from a genie, and it takes one of your cat’s nine lives each time you do it? We know that the Farm account must be a local admin when it’s provisioned. We also know that if the UPS and Central Admin are running on the same box (and they often are) that you need to do an IISRESET after it’s provisioned. Unfortunately most of us don’t leave our Farm account in the local admin group as a general rule, so the reprovisioning fails. The symptom of this is that profile syncs no longer run, and the two FIM services on the box running the UPS are set to “disabled.”
...
http://www.toddklindt.com/blog/Lists/Posts/Post.aspx?List=56f96349-3bb6-4087-94f4-7f95ff4ca81f&ID=275&Web=48e6fdd1-17db-4543-b2f9-6fc7185484fc