Using paged results, between 2.2.26 and 2.3.38.

I've got a number of auditing/update/query programs that make use of the paged results extension for large queries

Since upgrading the server to 2.3.38 from 2.2.26, all these programs have broken; they can retrieve the first page of results, but any attempt top fetch the next page results in a "paged results cookie is invalid or old" error. The client programs and the server platform (Redhat AS3) are both unaltered between server versions.

I can't find any references to changes with respect to paged results in CHANGES, except for the deadlock in bdb problem being fixed.

Would anyone be able to provide some advice for debugging this, perhaps being able to see the cookie being assigned by the server and what the client is offering back?