Had some trouble after the upgrade as every page was coming up "forbidden" or "missing" even when htaccess was deleted.
Apparently there was a stray virtual host leftover from another IP range our VPS vendor must use as a template for the VPS build in httpd.conf
Note to self: pay attention to litespeed's errors!
Deleted the bad virtualhost entry and it starting working right.
I still get this warning even from 3.1.1 and never had been able to figure it out:
ERROR [[HTAccess]] rewrite: unknown server variable while parsing: sessionid
except "sessionid" doesn't appear in any of our htaccess files. Weird.
Doesn't affect operation though.