You can either retrieve the message or place your call and retrieve the message at a later date. The Message Waiting Light option gives users a visual indication when there is a new message in their mailbox. Talk to your department STAR about which option might be best for you. My department has an intercom group for the multi line sets. Intercom groups are a great way for people in the same department to reach one another by dialing a 2-digit assigned number for each set.
Single line set users can also utilize the intercom feature.
In fact, a departmental intercom group can include a mix of single and multi line sets. Intercom group numbers are assigned through the Stanford telephone switch. Talk to your department STAR about the best intercom configuration for your department. My telephone is set to forward calls to my voice mailbox after 4 rings. I'm away from my office a lot.