IIRC it was initially developed for some version of SunOS.

Edit: here's the list of supported platforms, from the 1.09 tarball:

		alpha-dec-osf1
		i386-bsd4.3
		i386-force_cpu386-none
		i386-gnu (for Hurd development only)
		i386-isc2.2
		i386-isc3
		i386-sco3.2
		i386-sco3.2v4
		i386-sequent-bsd
		i386-sysv
		i386-sysv4
		i960-nindy960-none
		m68k-hp-bsd4.3
		m68k-mvme135-none
		m68k-mvme136-none
		m68k-sony-newsos3
		m68k-sony-newsos4
		m68k-sun-sunos4
		mips-dec-ultrix4
		mips-sgi-irix4
		sparc-sun-solaris2
		sparc-sun-sunos4

> I don't know why anyone would call it that.

It was a tongue in cheek remark, given how projects that don't want to pay that tax get accused of being in violation of said philosophy :-)