LightRoom 2.1 and Camera Raw 5.1

I noticed that the About... dialogue of LightRoom 2.1 indicates that Camera Raw 4.6 is installed; now that Camera Raw 5.1 is released with all exiting features, how can we get LightRoom 2.x to benefit from that? How do we add Camera Raw 5.1 to LightRoom 2.x?

=== Update ===
Sorry, it is a non-issue, Camera Raw 4.6 and 5.1 are identical or compatible: http://lightroom-blog.com/2008/10/updating-lightroom-21-to-camera-raw-51.html

Hi,
Lightroom shows camera Raw 4.6 as the one being used, in fact it's Camera Raw 5.1 that lightroom is useing and this little bug will be changed on the next update, this info supplied by Adobe.