openacs works just fine on 4.0 with no patching. The reason
none of the docs mention using it is that the official release
of 4.0 only happened 3 days ago.
The only change in install stuff is that you have to include
the nsdb module and "package require tdom" rather than
using nstdom (well besides building 4.0 which changed a lot
as tcl has been broken out and aolserver is just linked against the standard tcl libs...).
Btw, where was that documentation from? We should probably update it.