When I select menu on my samsung moment there is no messaging to select. When i selsect menu the only option are:add, wallpaper, search, notifications, and settings. There is no way to forward text messages or even send the same text to more than one person that I can see. I have had other people look at my phone and they were unable to see anyway to do this as well.
I was trying to figure out how to do the same thing! If you press the picture without picking up your finger, a pop-up box will appear with the option to forward. Hope this helps!
The question you asked isn't necessarily specific to the Moment because the stock Android messaging application will be similar across all Android devices. If the Android stock messaging application is not to your liking, you may want to consider a different messaging application from the Android market.