Mark multiple items as Despatched

Is there a way to change multiple items to the status 'Despatched'? At the moment I'm going to the 'Processing' link on the admin console home page and then changing the status of each individual item. It would save so much time if there was a way to select multiple or all items and change their statuses in one go.
Any help or guidance would be appreciated.

There is no builtin function for what you want

There is a Quick Status Update modification available, so you dont have to open each order individually, you can select an order and update it from the order list page. That would be a good starting point for you to create your multiple update mod!

... or it might be enough of a timesaver that you don't need to update multiple orders.

Go to the top of the page and click the "Plugins" link. then type "Quick Status Update" in the search box.

If you are really running 1.3.8 as your post suggests, you also need to upgrade right away; there are a number of well-known bugs in that release which expose your site to hackers.