I couldn’t find this documented anywhere, so I thought it might be worth mentioning that you can move a Time Machine database from one disk to another using Disk Utility. Using the Restore feature in Disk Utility, you can “restore” the Time Machine disk to another disk and retain the history of changes. This could be useful if you’ve outgrown your Time Machine backup drive, and want to migrate your existing backups to a new, larger drive. You should turn Time Machine off before doing starting this process, of course.
Be aware that the disks will have the same name and information, so it might confuse Time Machine. For example, after I activated Time Machine on the newly-created disk, I plugged in the old disk, and it showed up as a Time Machine drive, but the backup failed. It’s probably best to avoid having both of them plugged in. At the very least, rename one of them.
Perhaps more importantly, Carbon Copy Cloner 2.3 doesn’t work correctly for cloning a Time Machine drive (I don’t know about 3.x), as it doesn’t copy hard links but rather, copies what the links point to. This results in a lot of copies of your system when the Time Machine database has been around for a while.
Eine bessere Anleitung findet sich hier: http://njmac.blogspot.com/2008/11/move-time-machine-backups-to-new-volume.html