The only software I know providing ExtFS support under Mac OSX, and it works for me. Easy to use. Though the price is a little bit high, I think the software worth it.
Unable to work on my hackintosh build, but NTFS for Mac works well, sigh. You can give it a try to see if it works on your Mac OS.
I can get full access to ext2/ext3/ext4 file system, that’s good
Mac OS X 10.6 allows to read and write NTFS partitions, but the data writting performance is very bad, a few copies of the film might as well buy GB disc faster to the streets. So I bought Paragon NTFS for Mac OS X
The speed of using ntfs-3g is good under Linux. It's faster than windows
But I prefer to the network transmission, not much slower