I\'m in the in the process of developing an application for a client, which will have an SSL certificate and be served under https. However, to integrate with their existing
If your page is being accessed using https://www.example.com/main/index.jsp (SSL) then your browser will complain with "This page contains both secure and insecure items" if there are any resources in the HTML code that are referenced with http:// (non-SSL). This includes iframes.
If your navigation page is hosted on the same server then you can prevent the "insecure content" message by using a relative URL like this...
From your question it sounds like your navigation page is being served from a separate host and you're being forced to use something like this
which will of course cause the "insecure content" message in your browser.
Your only solutions are to either
implement SSL on the server holding your navigation page so you can use https:// for your iframe reference, or
move the navigation application to the same server so you can use a relative URL.
Personally I can't see why your navigation would be on a different host because then you're going to get JavaScript cross-domain scripting issues (unless some funky JSONP is involved).