libbz2.lib is build from bzip2/libbzip2 version 1.0.6 of 6 September 2010,
by Digital Mars Compiler Version 8.42n with the following commands

  $ dmc -c -o {blocksort,huffman,crctable,randtable,compress,decomporess,bzlib}.c
  $ lib -c libbz2.lib *.obj

bzlib.d is a hand written translation of bzlib.h.