Comment 8 for bug 719129

Right, that's why gparted should not pass -P and change the default behavior. It should just let dmraid use the name it wants, and follow along. On Maverick and before, Ubuntu has patched dmraid to never add the 'p'. We dropped that patch in Natty, but now it sounds like either both dmraid and parted need patched to only add the 'p' when the last character was already a digit. Or patching kpartx/multipath-tools to always add the 'p' so that they are in agreement would work too.

Whether the 'p' is added always or only when the last character is a digit, either way gparted needs to not pass -P to dmraid and alter its normal behavior, or you end up with duplicate devices.