Cygwin でビルド挑戦中なんですが、
gonzui-0.4.tar.gz で configure は通ったあと make すると、
(irb で require 'bdb' は true が返りました)

Making all in webapp
make[2]: Entering directory `/cygdrive/d/home/tmp/gonzui-0.4/gonzui/webapp'
rm -f xmlformatter.so
gcc -shared -s -Wl,--enable-auto-import,--export-all -o xmlformatter.so xmlforma tter.o -lcrypt
xmlformatter.o(.text+0xda): In function `xmlformatter_write_obj':
/cygdrive/d/home/tmp/gonzui-0.4/gonzui/webapp/xmlformatter.c:54: undefined refer ence to `_rb_obj_as_string'
xmlformatter.o(.text+0x1c3):/cygdrive/d/home/tmp/gonzui-0.4/gonzui/webapp/xmlfor matter.c:51: undefined reference to `_rb_id2name'
xmlformatter.o(.text+0x232): In function `xmlformatter_s_allocate':
/cygdrive/d/home/tmp/gonzui-0.4/gonzui/webapp/xmlformatter.c:92: undefined refer ence to `_rb_data_object_alloc'
xmlformatter.o(.text+0x259): In function `xmlformatter_initialize':
/cygdrive/d/home/tmp/gonzui-0.4/gonzui/webapp/xmlformatter.c:98: undefined refer ence to `_rb_check_type'
...(中略)...
matter.c:191: undefined reference to `_rb_define_method'
xmlformatter.o(.text+0x640):/cygdrive/d/home/tmp/gonzui-0.4/gonzui/webapp/xmlfor matter.c:192: undefined reference to `_rb_define_method'
xmlformatter.o(.text+0x56c): In function `xmlformatter_format':
/cygdrive/d/home/tmp/gonzui-0.4/gonzui/webapp/xmlformatter.c:181: undefined refe rence to `_rb_str_new'
collect2: ld returned 1 exit status
make[2]: *** [xmlformatter.so] Error 1
make[2]: Leaving directory `/cygdrive/d/home/tmp/gonzui-0.4/gonzui/webapp'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/cygdrive/d/home/tmp/gonzui-0.4/gonzui'
make: *** [all-recursive] Error 1

と出て失敗してしまいます。
どなたか原因わかりますでしょうか？