i found that last week when looking into the first occurrence but it didnt seem to help
/tmp/lshttpd/swap's permissions are ok. owned by lsws, the same user as litespeed is running as.
there are no other errors in any log files at the same time of each error.
the upload is not even attempted by the browser, a connection reset error is seen in the browser instantly.
as restarting lsws fixes the bug it also seems to suggest its not a file permission error.