Telnet Banner? SSH Post-Login Message?

I know how to add an SSH pre-login banner (and have done so).

What files do I add/modify to add a pre-login and a post-login banner/message for Telnet, and a post-login/greeting message for SSH?

In addition, can I use a C script to include variable content in these messages?

Something along the lines of:

Welcome (USER) to (SERVERNAME)
Your Last Login was (TIMESTAMP)
You are using (DISKUSAGE) of (DISKQUOTA)
You have (PINEMAIL_UNREAD) unread/new messages in your Pine account.

Bonus points if any of you have such a script already made to share.