at the right hand side of each group of messages and each individual message there is a checkbox, there’s also one right at the top for all your messages (next to the “total messages : xx” text

you can use the boxes to select all messages, all messages in certain time groups (today, 1 day old, 2 days old etc)

then right at the bottom of the message table there’s a drop down box with various options; one of (the second) is delete.

1. select the messages you want to delete
2. select “delete” from the dropdown box
3. click “go”

that should do it…