jails, ipfilter & stunnel

[V. Jones]

I'm setting up a server where I plan to use Jails to improve security
I also have installed and am configuring ipfilter.  Here are my 
questions:

Because I'm using Jails, I will have to have multiple ip aliases on the
network interface.  I will use ipfilter to specify what can go to each 
of the addresses.  (e.g., allow only incoming to port 80 on the jail 
running apache).  

Another jailed server will run mail services (pop, smtp, imap).  If 
I want to allow users to use web based email(over ssl of course), the 
web server  will have to communicate with the mail server.    Is there 
a chance of "information leakage" in this type of setup?

Finally, I'd like to use SSL to offer secure web connections & secure email
without having to buy two certificates.  Am I getting too cute if I accept 
ssl connections on  one ip address and use stunnel to route them to the 
appropriate jailed server?