River display of photo commenting!


How can I prevent this,

N.M.  posted a comment on the photo 5454_1192796262609_1309477984_525231_8268778_n

It happens when user does not provide any name to the photo!

Is there any way to give a default name IF the user did not provide name?

Say, like this

N.M comment the photo, here!

Thanks for your time.