This patch comes from in-house and this is Solaris 11 UR specific patch.

--- groff-1.22.2/src/preproc/preconv/preconv.cpp.org	2015-01-03 23:48:25.219040756 -0800
+++ groff-1.22.2/src/preproc/preconv/preconv.cpp	2015-01-03 23:48:54.304173930 -0800
@@ -34,9 +34,9 @@
 #if HAVE_ICONV
 # include <iconv.h>
 # ifdef WORDS_BIGENDIAN
-#  define UNICODE "UTF-32BE"
+#  define UNICODE "UCS-4BE"
 # else
-#  define UNICODE "UTF-32LE"
+#  define UNICODE "UCS-4LE"
 # endif
 #endif