Patch by Robert Scheck <robert@fedoraproject.org> for iftop >= 1.0pre4 which fixes
the regression introduced with 1.0pre4 resulting in a broken MAC address output.
This patch was proposed to upstream at Mon, 20 Jan 2014 01:58:57 +0100. See also
the following links for details:

 - https://bugzilla.redhat.com/show_bug.cgi?id=1063298
 - https://bugzilla.redhat.com/show_bug.cgi?id=1165349

--- iftop-1.0pre4/iftop.c			2014-01-19 21:21:19.000000000 +0100
+++ iftop-1.0pre4/iftop.c.mac-address		2014-01-20 01:55:16.000000000 +0100
@@ -55,7 +55,7 @@
 
 /* ethernet address of interface. */
 int have_hw_addr = 0;
-char if_hw_addr[6];    
+unsigned char if_hw_addr[6];    
 
 /* IP address of interface */
 int have_ip_addr = 0;