It used to be that Ctrl + - and Ctrl + + would increase or decrease the text size of the terminal in earlier versions of Ubuntu, which is helpful when you're giving presentations and want to show your code in a larger size. I switched to Xubuntu 12.04, and I'm missing these keyboard shortcuts.

Is there an alternative I can use? Or if not, is there a way I can define my own shortcut to replace these?

Update: Happy to report that this question is now moot for recent versions of xfce4-terminal! See here.