A very simple but ugly hack to link to Git comment ids from a Bugzilla comment.

bugzilla-comment-git-id.patch

--- Template.pm.orig	2010-10-20 17:16:02.000000000 -0700
+++ Template.pm	2010-10-20 17:59:23.000000000 -0700
@@ -234,6 +234,25 @@
                ("\0\0" . ($count-1) . "\0\0")
               ~egmxi;
 
+    # Link to Git repository
+    if ($text =~ /\bcommit\s*[a-zA-Z0-9]+/) {
+        my $gitweb = "http://example.com/git";
+        my %repos = (
+            "2" => "product2.git",
+            "3" => "product3.git",
+            "5" => "product5.git",
+            "6" => "product6.git"
+            );
+        my $dbh = Bugzilla->dbh;
+        my ($product_id) =
+            $dbh->selectrow_array('SELECT product_id FROM bugs WHERE bug_id = ?',
+                                  undef, $curr_bugid);
+        my $repo = $repos{$product_id};
+        if ($repo) {
+            $text =~ s#\b(commit\s*)([a-zA-Z0-9]+)#$1<a href="$gitweb/?p=$repo;a=commit;h=$2">$2</a>#ig;
+        }
+    }
+
     # Current bug ID this comment belongs to
     my $current_bugurl = $curr_bugid ? "show_bug.cgi?id=$curr_bugid" : "";