Yes i was looking at the idea of combining the certificates into one and putting it on the sme server, that would in theory solve the issue.
It's not a problem at the client end as such but the server end not matching up (i.e the client is given a certificate from sme1 but url for the internal server, and traffic passed to internal-server1, the client therefore has a url that is on the internal server certificate but the certificate of the sme server which it throws out).
eg url -
https://server1.domain.comreceives certificate that says sme.domain.com
If i can get the certifcates for the different uses i want combined then hopefully the proxy pass will work.
Ideally i was hoping to have the equivalent of port forwarding to route the traffic straight to the required servers, but different destinations for different urls, but i'm not sure this is actually feasible.