Adding a new secure port to Proxy Server Squid 3

[odracir]

Hello,

I´m having a bit of a problem with my webmail using the proxy server (squid 3).
We did some security changes in our webmail service that is located in another branch. We added port 7733 to make it more secure but the proxy server does not allow this port to go through.
Before we use to login using: https://mymailserver.com and now it is  https://mymailserver.com:7733

Is there a way to allow port 7733 to be accepted by the proxy server?
I tried adding the port to "acl safeports" and "acl sslports" in the access control tab in the proxy server but it didn't work.

Thanks in advance for your help.