anyone recommend a way to autocomplete usernames when using the 'mention' function in elgg?

i use the 'mentions' plugin on my site and no-one really understands how to use it intuitively. it would be much better if an autocomplete dropdown appeared in textboxes when the @ symbol is typed, just as wiretools currently allows within the wire's add box. does anyone know of a plugin that adds this feature to blog text, discussions and comments etc?