The stable series lives in the branch lighttpd-1.4.x, check it out:

	svn checkout svn://svn.lighttpd.net/lighttpd/branches/lighttpd-1.4.x

The current development version is lighttpd2 at http://git.lighttpd.net/lighttpd/lighttpd2.git, clone it:

	git clone git://git.lighttpd.net/lighttpd/lighttpd2.git

The previous trunk (aka "1.5") has been dead for some time, and is archived as svn://svn.lighttpd.net/lighttpd/branches/lighttpd-1.5-dead