Try fixing the SunOS build, from Ingo Schwarze (upstream).

textproc/mdocml/distinfo

@@ -1,8 +1,11 @@
-$NetBSD: distinfo,v 1.28 2013/10/05 14:48:15 wiz Exp $
+$NetBSD: distinfo,v 1.29 2013/10/06 15:48:42 wiz Exp $
 
 SHA1 (mdocml-1.12.2.tar.gz) = 6a86cc4f373bcc51aa8bf1a7499db368e977a166
 RMD160 (mdocml-1.12.2.tar.gz) = 8fcd1b9dd20b3a2eee9412d210e1b994c9ae7c17
 Size (mdocml-1.12.2.tar.gz) = 286400 bytes
 SHA1 (patch-Makefile) = 30ae6393f1af5995735fb98c9bbfa53f22cdc0a8
+SHA1 (patch-apropos__db.c) = fa26351e17a465dd1b89854903f3c04408440d47
+SHA1 (patch-config.h.post) = 23b57b1c20e02733a12acbe7a62c5113cc245ecd
+SHA1 (patch-mandocdb.c) = 6c376bff856ab48f16721e589e71ce7b981a802b
 SHA1 (patch-preconv.1) = 92787c58f451e1d247a25bbe136f188bf42e4c73
 SHA1 (patch-roff.7) = a8daeae7e8e6c0117d499fb0c4a848d724b29b3e

textproc/mdocml/patches/patch-apropos__db.c

@@ -0,0 +1,29 @@
+$NetBSD: patch-apropos__db.c,v 1.1 2013/10/06 15:48:42 wiz Exp $
+
+--- apropos_db.c.orig	2013-10-05 14:09:07.000000000 +0000
++++ apropos_db.c
+@@ -30,14 +30,19 @@
+ #include <string.h>
+ #include <unistd.h>
+ 
+-#if defined(__linux__)
+-# include <endian.h>
+-# include <db_185.h>
+-#elif defined(__APPLE__)
++#if defined(__APPLE__)
+ # include <libkern/OSByteOrder.h>
+-# include <db.h>
++#elif defined(__linux__)
++# include <endian.h>
++#elif defined(__sun)
++# include <sys/byteorder.h>
+ #else
+ # include <sys/endian.h>
++#endif
++
++#if defined(__linux__)
++# include <db_185.h>
++#else
+ # include <db.h>
+ #endif
+ 

textproc/mdocml/patches/patch-config.h.post

@@ -0,0 +1,14 @@
+$NetBSD: patch-config.h.post,v 1.1 2013/10/06 15:48:42 wiz Exp $
+
+--- config.h.post.orig	2013-10-05 14:09:07.000000000 +0000
++++ config.h.post
+@@ -19,6 +19,9 @@
+ #  if defined(__APPLE__)
+ #    define betoh64(x) OSSwapBigToHostInt64(x)
+ #    define htobe64(x) OSSwapHostToBigInt64(x)
++#  elif defined(__sun)
++#    define betoh64(x) BE_64(x)
++#    define htobe64(x) BE_64(x)
+ #  else
+ #    define betoh64(x) be64toh(x)
+ #  endif

textproc/mdocml/patches/patch-mandocdb.c

@@ -0,0 +1,34 @@
+$NetBSD: patch-mandocdb.c,v 1.4 2013/10/06 15:48:42 wiz Exp $
+
+--- mandocdb.c.orig	2013-10-05 14:09:07.000000000 +0000
++++ mandocdb.c
+@@ -34,19 +34,21 @@
+ #include <string.h>
+ #include <unistd.h>
+ 
+-#if defined(__linux__) || defined(__sun)
+-# include <endian.h>
+-# include <db_185.h>
+-#elif defined(__APPLE__)
++#if defined(__APPLE__)
+ # include <libkern/OSByteOrder.h>
+-# include <db.h>
++#elif defined(__linux__)
++# include <endian.h>
++#elif defined(__sun)
++# include <sys/byteorder.h>
++# include <sys/stat.h>
+ #else
+ # include <sys/endian.h>
+-# include <db.h>
+ #endif
+ 
+-#if defined(__sun)
+-#include <sys/stat.h>
++#if defined(__linux__)
++# include <db_185.h>
++#else
++# include <db.h>
+ #endif
+ 
+ #include "man.h"