Description of problem: Multipath-tools should probably be part of Core. It is more advanced than the simple-minded mdmpd: It's not a final release yet, but IMHO it's already worth of getting some attention by at least Rawhide users. Additional info: http://christophe.varoqui.free.fr/wiki/wakka.php?wiki=Home
Am I right in assuming that mp-tools depends on a kernel module (and thus patches) not in Rawhide/upstream yet? And mdmpd relies on md while multipathd on dm, right? I guess that would be another justification for multipath-tools' inclusion. Those pesky two-letter acronyms... thankfully we have run out of possible permutations of 'm' and 'd'.
multipath-tools indeed depends on a device-mapper module that is not yet upstream, but it will probably be submitted within the next couple of months.
Deferring because of kernel dependency.
I have started work on this - I named the package device-mapper-multipath to avoid confusion with alternative multipath implementations. I anticipate the kernel patches will be included as of 2.6.12.