diff -ruN man-1.6g.orig/src/makewhatis.sh man-1.6g/src/makewhatis.sh
--- man-1.6g.orig/src/makewhatis.sh	2007-09-17 20:35:14.000000000 +0200
+++ man-1.6g/src/makewhatis.sh	2012-04-10 09:41:19.910191721 +0200
@@ -230,7 +230,7 @@
 	    find $mandir/${pages}$i/. -name '*' $findarg0 $findarg -print | $AWK '
 
 	    function readline() {
-              if (use_zcat || use_bzcat || use_lzcat) {
+              if (use_zcat || use_bzcat || use_lzcat || use_xzcat) {
 		result = (pipe_cmd | getline);
 		if (result < 0) {
 		  print "Pipe error: " pipe_cmd " " ERRNO > "/dev/stderr";
@@ -245,7 +245,7 @@
 	    }
 	    
 	    function closeline() {
-              if (use_zcat || use_bzcat || use_lzcat) {
+              if (use_zcat || use_bzcat || use_lzcat || use_xzcat) {
 		return close(pipe_cmd);
 	      } else {
 		return close(filename);
@@ -260,8 +260,10 @@
 		print "adding " filename > "/dev/stderr"
 	      }
 	      
-	      use_zcat = match(filename,"\\.Z$") ||
-			 match(filename,"\\.z$") || match(filename,"\\.gz$");
+          use_xzcat = match(filename,"\\.xz");
+          if (!use_xzcat)
+	         use_zcat = match(filename,"\\.Z$") ||
+			        match(filename,"\\.z$") || match(filename,"\\.gz$");
 	      if (!use_zcat)
 		use_bzcat = match(filename,"\\.bz2");
               if(!use_bzcat)
@@ -279,8 +281,10 @@
 		actual_section = section;
 	      }
 	      sub(/\..*/, "", progname);
-              if (use_zcat || use_bzcat || use_lzcat) {
-		if (use_zcat) {
+              if (use_zcat || use_bzcat || use_lzcat || use_xzcat) {
+          if (use_xzcat) {
+              pipe_cmd = "xzcat \"" filename "\"";
+          } else if (use_zcat) {
 		  pipe_cmd = "zcat \"" filename "\"";
                 } else if (use_bzcat) {
 		  pipe_cmd = "bzcat \"" filename "\"";