diff --git a/builtin/commit.c b/builtin/commit.c
index 6c09857a60..22ba54f9bb 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -70,7 +70,6 @@ static const char *logfile, *force_author;
 static const char *template_file;
 static char *edit_message, *use_message;
 static char *fixup_message, *squash_message;
-static char *author_name, *author_email, *author_date;
 static int all, edit_flag, also, interactive, only, amend, signoff;
 static int quiet, verbose, no_verify, allow_empty, dry_run, renew_authorship;
 static int no_post_rewrite, allow_empty_message;
@@ -462,7 +461,7 @@ static int is_a_merge(const unsigned char *sha1)
 
 static const char sign_off_header[] = "Signed-off-by: ";
 
-static void determine_author_info(void)
+static void determine_author_info(struct strbuf *author_ident)
 {
 	char *name, *email, *date;
 
@@ -506,10 +505,8 @@ static void determine_author_info(void)
 
 	if (force_date)
 		date = force_date;
-
-	author_name = name;
-	author_email = email;
-	author_date = date;
+	strbuf_addstr(author_ident, fmt_ident(name, email, date,
+					      IDENT_ERROR_ON_NO_NAME));
 }
 
 static int ends_rfc2822_footer(struct strbuf *sb)
@@ -553,10 +550,21 @@ static int ends_rfc2822_footer(struct strbuf *sb)
 	return 1;
 }
 
+static char *cut_ident_timestamp_part(char *string)
+{
+	char *ket = strrchr(string, '>');
+	if (!ket || ket[1] != ' ')
+		die("Malformed ident string: '%s'", string);
+	*++ket = '\0';
+	return ket;
+}
+
 static int prepare_to_commit(const char *index_file, const char *prefix,
-			     struct wt_status *s)
+			     struct wt_status *s,
+			     struct strbuf *author_ident)
 {
 	struct stat statbuf;
+	struct strbuf committer_ident = STRBUF_INIT;
 	int commitable, saved_color_setting;
 	struct strbuf sb = STRBUF_INIT;
 	char *buffer;
@@ -679,14 +687,13 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 
 	strbuf_release(&sb);
 
-	determine_author_info();
+	/* This checks and barfs if author is badly specified */
+	determine_author_info(author_ident);
 
 	/* This checks if committer ident is explicitly given */
-	git_committer_info(0);
+	strbuf_addstr(&committer_ident, git_committer_info(0));
 	if (use_editor && include_status) {
-		char *author_ident;
-		const char *committer_ident;
-
+		char *ai_tmp, *ci_tmp;
 		if (in_merge)
 			fprintf(fp,
 				"#\n"
@@ -714,23 +721,21 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 		if (only_include_assumed)
 			fprintf(fp, "# %s\n", only_include_assumed);
 
-		author_ident = xstrdup(fmt_name(author_name, author_email));
-		committer_ident = fmt_name(getenv("GIT_COMMITTER_NAME"),
-					   getenv("GIT_COMMITTER_EMAIL"));
-		if (strcmp(author_ident, committer_ident))
+		ai_tmp = cut_ident_timestamp_part(author_ident->buf);
+		ci_tmp = cut_ident_timestamp_part(committer_ident.buf);
+		if (strcmp(author_ident->buf, committer_ident.buf))
 			fprintf(fp,
 				"%s"
 				"# Author:    %s\n",
 				ident_shown++ ? "" : "#\n",
-				author_ident);
-		free(author_ident);
+				author_ident->buf);
 
 		if (!user_ident_sufficiently_given())
 			fprintf(fp,
 				"%s"
 				"# Committer: %s\n",
 				ident_shown++ ? "" : "#\n",
-				committer_ident);
+				committer_ident.buf);
 
 		if (ident_shown)
 			fprintf(fp, "#\n");
@@ -739,6 +744,9 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 		s->use_color = 0;
 		commitable = run_status(fp, index_file, prefix, 1, s);
 		s->use_color = saved_color_setting;
+
+		*ai_tmp = ' ';
+		*ci_tmp = ' ';
 	} else {
 		unsigned char sha1[20];
 		const char *parent = "HEAD";
@@ -754,6 +762,7 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 		else
 			commitable = index_differs_from(parent, 0);
 	}
+	strbuf_release(&committer_ident);
 
 	fclose(fp);
 
@@ -1278,6 +1287,7 @@ static int run_rewrite_hook(const unsigned char *oldsha1,
 int cmd_commit(int argc, const char **argv, const char *prefix)
 {
 	struct strbuf sb = STRBUF_INIT;
+	struct strbuf author_ident = STRBUF_INIT;
 	const char *index_file, *reflog_msg;
 	char *nl, *p;
 	unsigned char commit_sha1[20];
@@ -1308,7 +1318,7 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
 
 	/* Set up everything for writing the commit object.  This includes
 	   running hooks, writing the trees, and interacting with the user.  */
-	if (!prepare_to_commit(index_file, prefix, &s)) {
+	if (!prepare_to_commit(index_file, prefix, &s, &author_ident)) {
 		rollback_index_files();
 		return 1;
 	}
@@ -1387,11 +1397,11 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
 	}
 
 	if (commit_tree(sb.buf, active_cache_tree->sha1, parents, commit_sha1,
-			fmt_ident(author_name, author_email, author_date,
-				IDENT_ERROR_ON_NO_NAME))) {
+			author_ident.buf)) {
 		rollback_index_files();
 		die("failed to write commit object");
 	}
+	strbuf_release(&author_ident);
 
 	ref_lock = lock_any_ref_for_update("HEAD",
 					   initial_commit ? NULL : head_sha1,
diff --git a/ident.c b/ident.c
index 9e2438826d..1c4adb0a9a 100644
--- a/ident.c
+++ b/ident.c
@@ -217,8 +217,10 @@ const char *fmt_ident(const char *name, const char *email,
 	}
 
 	strcpy(date, git_default_date);
-	if (!name_addr_only && date_str)
-		parse_date(date_str, date, sizeof(date));
+	if (!name_addr_only && date_str && date_str[0]) {
+		if (parse_date(date_str, date, sizeof(date)) < 0)
+			die("invalid date format: %s", date_str);
+	}
 
 	i = copy(buffer, sizeof(buffer), 0, name);
 	i = add_raw(buffer, sizeof(buffer), i, " <");
diff --git a/t/t7501-commit.sh b/t/t7501-commit.sh
index 8297cb4f1e..8980738c75 100755
--- a/t/t7501-commit.sh
+++ b/t/t7501-commit.sh
@@ -230,6 +230,10 @@ test_expect_success 'amend commit to fix date' '
 
 '
 
+test_expect_success 'commit complains about bogus date' '
+	test_must_fail git commit --amend --date=10.11.2010
+'
+
 test_expect_success 'sign off (1)' '
 
 	echo 1 >positive &&