06-25-2014 12:10 PM
First, full disclosure: I don't own a PlayBook.
On a PC, multiple items can be selected by holding the Ctrl button and clicking on the desired items. First of all, I'm not sure if there's a Ctrl button on the PlayBook but if there is, how about trying that method?
I hope that helps you (but I'm betting it didn't).
06-26-2014 11:05 AM
Swipe down from the top bezel, and you will see an icon that is two dot rectangles ontop of each other named select, tap this and then select any messages you want to heart content