Forum OpenACS Q&A: Response to AOLserver 3.5
However, while it's not reflected in the ChangeLog in cvs (yet?), nor as far as I recall announced to the list, from the cvs log it looks like there have been a lot of commits to the 3.5 branch in the last couple weeks, including things like fixes to that binary file upload bug. So my guess is most problems people have had with 3.5 will probably go away if you get the latest version out of cvs.
And yes, according to the AOL folks, 3.5 is supposed to be feature equivalent to 3.4.2, but with the old 3.x build process for the Tcl stuff ripped out and replaced with the "use the stock Tcl distribution" build process from 4.0. Plus a few other 4.0-style changes like putting all the docs into man page format.
That's what I understood anyway. But again from the 3.5 cvs log comments, it looks like they're back-porting some other 4.0 features into 3.5 as well. For example:
2002-10-14 19:21 jgdavidson * nsd/tclsock.c: Updated to work without a server.
That sounds related to the AOLserver 4.0 ability to load libnsd.so into a tclsh and be used without running AOLserver per-se at all. So I suspect they're putting in the work to have the 3.5 codebase track the 4.0 codebase at least somewhat more closely. If you really wanted to know for sure, of course the thing to do would be to ask the AOL folks (Jim, Kriston, etc.) directly.