apache2 and ssl accelerator

I have squid functioning nicely as a https accelerator for tomcat6 and IIS7 (Outlook web access and terminal server gateway), and now I want to publish a mantis server that way too. The problem is that squid takes the https request and proxies it as a http request to the server running mantis. apache2 gets the http request and so any hard links in there are prepended with http, which doesn't work (eg browser tries to get css via http which isn't reachable). Squid is adding the front-end-https header to the requests which should tell apache that the front end request was https:// but it doesn't seem to be working. What do I need to do to make apache understand that the user request was https not http? Thanks James