This is basically a patch to the flymake.el file. Normally it would underline errors and then show you the message when you hover the mouse over it. I really hate using a mouse so I decided I wanted to show this differently, so I patched the source and now it'll show you the error messages right behind the position where they occur.
I cannot guarantee this'll work without tweaking, but it is a start, and you can always ask me for directions on installing this.
browse here