Try downloading the most recent NTFS-3G. I haven't done much testing with NTFS-3G on Lion as I use Tuxera NTFS. NTFS-3G is the free version supported by Tuxera, I believe, so they may have an updated installer.
The 2011.4.1 version of Tuxera does work with Lion so if the reinstall of NTFS-3G doesn't work, then you may want to try installing the trial of Tuxera NTFS, then uninstall Tuxera, just to get rid of the error message. (Of course, you could also buy Tuxera NTFS. 🙂 I use Tuxera NTFS because I got issues when copying very large files to the NTFS partition. Over 25GB. Tuxera is more reliable in that regard.)