[Plugin: NextGEN Gallery] How to add WP 2.9’s “Set post thumbnail” function to NextGen?

With WordPress 2.9 it is possible to directly set a “post thumbnail” for every post/page. However it is only available to do so by clicking a link in WP’s own media manager interface. I wish it is integrated to NextGen which IMHO should not be very difficult. Bur for now is there any easy way to manually add this “link” (or rather “function”)? Thanks in advance.

https://www.ads-software.com/extend/plugins/nextgen-gallery/