No, I think he means longer. IN-ADDR.ARPA can only be delegated on octet
boundaries, so IN-ADDR for /16 and shorter prefixes will be delegated in /16
chunks. IN-ADDR for prefixes longer than /16 must still be maintained by the
root, since they cannot be delegated.
this is a very bad thing, since it forces an ip NETWORK provider also
to deal with the DNS of its customers, not just to assign a pointer to
when is this problem solved? with ipv6?
No, the problem is solved, just not widely deployed. There is no requirement
to delegate on octet bounds anymore.