I agree with you njok, and the keyboard is right there. (On the other hand, this is one feature where almost all e.readers come up short, so iRiver's not alone on this.)
Unfortunately, iRiver doesn't seem to comment on what it might or might not be working on. (Most developers don't, so no surprises there, but it would be nice if they did.) But iRiver doesn't seem to be very info-generous as a rule.
Have you tried writing your suggestions to iRiver? I did, raising a couple of points where I felt the functions could definitely be improved, and unfortunately got a very non-committal reply saying in essence only "That's just how it works", but every bit of feedback helps build the incentive, surely.