Ooops. Sorry that's an old link that hasn't been updated since 4.40. From the download link, it looks like there are binaries for the BSD's and solaris 7, then a generic "linux" binary for 32-bit and 64-bit.
So I guess I'm not sure any linux OS's include it by default.
EDIT: the latest version of Damn Small Linux
still uses xfree86 4.2...