RewriteEngine On

RewriteCond %{DOCUMENT_ROOT}/.php81 -f
RewriteRule ^ - [H=application/x-httpd-lsphp81]

RewriteCond %{DOCUMENT_ROOT}/.php82 -f
RewriteRule ^ - [H=application/x-httpd-lsphp82]

RewriteCond %{DOCUMENT_ROOT}/.php83 -f
RewriteRule ^ - [H=application/x-httpd-lsphp83]

RewriteCond %{DOCUMENT_ROOT}/.php84 -f
RewriteRule ^ - [H=application/x-httpd-lsphp84]