webissues 1.1.4 not accessible over https

I have server with Webissues 1.1.4 where I setup ssl certificate and redirection in .htaccess in public_html:

RewriteEngine On
RewriteCond %{HTTPS} off
RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI} [R=301,L]

Under http://example.com webissues panel works perfectly but not under https://example.com. Above redirection works excellent for each site on the server. What is wrong, what to do, need help. ;)