Fix Makefile (ldd -v doesn't work on my ldd).
diff --git a/Makefile b/Makefile
index 19b5c54..6d73c1b 100644
--- a/Makefile
+++ b/Makefile
@@ -12,8 +12,8 @@
 MANDIR:=/usr/local/man
 INCDIR:=/usr/local/include
 
-# Need libc6 for this.  Should covert to autoconf.
-ifneq ($(shell ldd -v | fgrep 2.2),)
+# Need libc6 for this.  FIXME: Should covert to autoconf.
+ifneq ($(shell ldd --version 2>/dev/null | fgrep 2.2),)
 DO_IPV6=1
 endif