Scroll down to see how to do this in Symphony 1.5
In Symphony 2.0:
Hover over a message to show the timestamp and a check mark (figure 1).
Figure 1 Timestamp
Click the timestamp or check mark to see if the message was delivered and who read the message (figure 2).
Figure 2 See the message status
In Symphony 1.5:
Each message has a timestamp next to the name of the sender (Figure 1):
Figure 1 Timestamp
Click the timestamp to see if the message was delivered and who read the message under Message Status (Figure 2):
Figure 2 Read Receipts