I have to apologize for the lack of clarity since I was getting the
reports from customers. The problem is NOT in setting a prefix mask.
The problem is with inverse for subnets. From the install notes of
Windows/NT (DNS and Microsoft Windows NT 4.0) dated May 12, 1996 (page
28), under the section 'Configuring Reverse Lookup' the doc says, and
??? I haven't a clue. I think there is a bug???
The defacto standard for doing subnetting and inverse has been documented
in a draft standard:
I hope Microsoft can get this fixed since I have had to start allocating
/24s to very small sites in order to bypass this problem.