Added link to backend homepage.

unsupported/canon-pixma-mp750.html

@@ -35,7 +35,7 @@
     <h2>Comments</h2>
     <p>
       Christopher Albert <a
-      href="http://lists.alioth.debian.org/pipermail/sane-devel/2005-September/014718.html">has
+      href="http://cmp750.berlios.de/">has
       started working on a backend</a> for the MP750.
     </p>
     <p>