ZFS send/recv via ssh hangs

I was using the send/recv ZFS command to upload snaphots from a server to another via ssh.

There were no issue while both were running 10.3-RELEASE.

But, since I upgraded the receiver to 11-RELEASE, the process hangs while sending or receiving the 2nd set.

First set, root@mySnap is well processed and the zfs set is created.
Then, on attempt to send the next set, root/home@snap, the process looks stucked.

I didn't read anything harmfull about ZFS between the two release.
Did I miss something that said ZFS send/recv is not possible in that case ?