diff --git a/share/functions/man.fish b/share/functions/man.fish
index 2b9bab517..25c81a4bb 100644
--- a/share/functions/man.fish
+++ b/share/functions/man.fish
@@ -1,22 +1,23 @@
 function man --description "Format and display the on-line manual pages"
 
-	# Work around OS X's "builtin" manpage that everything symlinks to,
+	# Work around the "builtin" manpage that everything symlinks to,
 	# by prepending our fish datadir to man. This also ensures that man gives fish's
 	# man pages priority, without having to put fish's bin directories first in $PATH
-	# Temporarily set a MANPATH, unless one is set already
-	if not set -q MANPATH
-		set -l fish_manpath (dirname $__fish_datadir)/fish/man
-		if test -d "$fish_manpath"
-			# Notice local but exported variable
-			set -lx MANPATH "$fish_manpath":(command manpath)
-			
-			# Invoke man with this manpath, and we're done
-			command man $argv
-			return
-		end
+
+	# Notice local but exported variable
+	set -lx MANPATH (string join : $MANPATH)
+	if test -z "$MANPATH"
+		type -q manpath; and set MANPATH (command manpath)
+	end
+	set -l fish_manpath (dirname $__fish_datadir)/fish/man
+	if test -d "$fish_manpath" -a -n "$MANPATH"
+		set MANPATH "$fish_manpath":$MANPATH
+
+		# Invoke man with this manpath, and we're done
+		command man $argv
+		return
 	end
 	
-	# If MANPATH is set explicitly, or fish's man pages could not be found,
-	# just invoke man normally
+	# If fish's man pages could not be found, just invoke man normally
 	command man $argv
 end