diff --git a/commit-tree.c b/commit-tree.c
index 4fe64ce0b4..352ded104c 100644
--- a/commit-tree.c
+++ b/commit-tree.c
@@ -144,9 +144,9 @@ int main(int argc, char **argv)
 	time(&now);
 	realdate = ctime(&now);
 
-	gecos = getenv("COMMITTER_NAME") ? : realgecos;
-	email = getenv("COMMITTER_EMAIL") ? : realemail;
-	date = getenv("COMMITTER_DATE") ? : realdate;
+	gecos = getenv("AUTHOR_NAME") ? : realgecos;
+	email = getenv("AUTHOR_EMAIL") ? : realemail;
+	date = getenv("AUTHOR_DATE") ? : realdate;
 
 	remove_special(gecos); remove_special(realgecos);
 	remove_special(email); remove_special(realemail);
diff --git a/diff-tree.c b/diff-tree.c
index 5cf6057f45..1960c23561 100644
--- a/diff-tree.c
+++ b/diff-tree.c
@@ -180,7 +180,7 @@ int main(int argc, char **argv)
 		char *arg = argv[1];
 		argv++;
 		argc--;
-		if (!strcmp(arg, "-R")) {
+		if (!strcmp(arg, "-r")) {
 			recursive = 1;
 			continue;
 		}