What distribution (Ubuntu, Kubuntu, etc.) are you installing?
I've arranged for LVM partitions not to appear in the autopartitioner's disk selector, which was just a bug (specifically, bug 32845). You seem to be suggesting that there's a bug in the manual partitioner as well, though, so I need to know whether this is the GTK or the KDE frontend.
The bug here is really that LVM partitions are offered at all. LVM partitions are intentionally not supported by the live installer; we decided that we don't have time to do a reasonable job on this for Dapper, so it's better to disable support for them. The text-mode install CD still supports them.