[mistwang]

Originally Posted by aww

I've traced the additional nested htaccess errordocument issues to litespeed being overly aggressive on rewrite issues in the topmost .htaccess

however the issue is so complex that I am having difficultly producing a simple example - will have to work on it - note that the issues do not exist when apache is running, it interprets the nested rules perfectly

You can try turning on rewrite log by adding Apache directive "RewriteLogLevel 9" to the section of this vhost in your Apache httpd.conf. Send me the rewrite log and tell me which rewrite rule has been over processed along with the rewrite rules in your .htaccess files.