how to redirect https to new domain?

I redeveloped my company's website and I'm having some issues with redirecting / SSL

Typing or clicking on http://olddomain.org redirects just fine to https://newdomain.com.However, typing or clicking on the link https://olddomain.org does not redirect to https://newdomain.com and I get this error:

Firefox does not trust this site because it uses a certificate that is not valid for olddomain.org. The certificate is only valid for the following names: *.newdomain.com, newdomain.com

Is there some rewrite conditions I can put in my .htaccess file to fix this? Or is this an issue with the way that I set up the SSL certificate for the new domain?

Here's what I've tried so far:

<IfModule mod_rewrite.c>  RewriteEngine On  Redirect 301 / http://newdomain.com/</IfModule><br />

and

  RewriteEngine on  RewriteCond %{HTTP_HOST} ^(www\.)?http://olddomain\.org$  RewriteRule ^(.*)$ http://newdomain.com/$1 [R=301,QSA,L]