Growing a raid array online with different capacity disks

Hello,

I would like to be able to take out a disk from a raid-5 array and add
a higher capacity disk, with the raid array growing in size.

a-la drobo/synology/qnap nas systems.

i.e. 4x1tb disks, take out 1x1tb replace with 1x3tb disk, array grows

Does mdadm support this?

I searched the official faq and debian faq for expand and grow and
didn't find anything.

Thanks a lot.

jbp