What do you mean the stride is wrong? Is the set not using a 128 kb stride?
Parted and the text installer do not support dmraid devices properly yet. To install you will have to follow the howto at https://wiki.ubuntu.com/FakeRaidHowto -- DMRAID stopped to work in kernels > 2.6.15 https://launchpad.net/bugs/54246 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
