new file mode 100644
--- /dev/null
+++ b/mail_auth_wait.t
@@ -0,0 +1,161 @@
+#!/usr/bin/perl
+
+# (C) Maxim Dounin
+
+# Tests for nginx mail module for WAIT auth response.
+
+###############################################################################
+
+use warnings;
+use strict;
+
+use Test::More;
+
+BEGIN { use FindBin; chdir($FindBin::Bin); }
+
+use lib 'lib';
+use Test::Nginx;
+use Test::Nginx::IMAP;
+
+###############################################################################
+
+select STDERR; $| = 1;
+select STDOUT; $| = 1;
+
+local $SIG{PIPE} = 'IGNORE';
+
+my $t = Test::Nginx->new()->has(qw/mail imap http map rewrite/)
+	->write_file_expand('nginx.conf', <<'EOF');
+
+%%TEST_GLOBALS%%
+
+daemon off;
+
+events {
+}
+
+mail {
+    proxy_pass_error_message  on;
+    proxy_timeout  15s;
+    auth_http  http://127.0.0.1:8080/mail/auth;
+
+    server {
+        listen     127.0.0.1:8143;
+        protocol   imap;
+        imap_auth  plain cram-md5 external;
+    }
+}
+
+http {
+    %%TEST_GLOBALS_HTTP%%
+
+    map $upstream_http_count $reply {
+        # Each wait is 1 second, so wait 4 times, which should get us
+        # to after the sleep(3), but then after another sleep(2) we
+        # should have completed with a success
+
+        1 WAIT;
+        2 WAIT;
+        3 WAIT;
+        4 WAIT;
+        5 OK;
+
+        default ERROR;
+    }
+
+    log_format test "reply=$reply";
+
+    server {
+        listen       127.0.0.1:8080;
+        server_name  localhost;
+
+        access_log %%TESTDIR%%/auth.log test;
+
+        location = /mail/auth {
+            add_header Auth-Status $reply;
+            add_header Auth-Server 127.0.0.1;
+            add_header Auth-Port %%PORT_8144%%;
+            add_header Auth-Pass "";
+            add_header Auth-Wait 1;
+            proxy_pass http://127.0.0.1:8081;
+        }
+    }
+}
+
+EOF
+
+$t->run_daemon(\&Test::Nginx::IMAP::imap_test_daemon);
+$t->run_daemon(\&http_daemon);
+$t->run()->plan(4);
+
+$t->waitforsocket('127.0.0.1:' . port(8144));
+$t->waitforsocket('127.0.0.1:' . port(8081));
+
+###############################################################################
+
+# WAIT response
+
+my $s = Test::Nginx::IMAP->new();
+$s->read();
+$s->send('a01 LOGIN test@example.com wait');
+
+sleep(3);
+
+my $f = $t->read_file('auth.log');
+my @waits = $f =~ /^reply=WAIT/mg;
+ok(@waits >= 2, "found multiple WAIT responses in log");
+
+my @ready = $s->can_read(0.1);
+is(scalar @ready, 0, "nothing to read while waiting");
+
+sleep(2);
+
+@ready = $s->can_read(0);
+is(scalar @ready, 1, "ready for reading");
+
+$s->ok('login success after waiting');
+
+###############################################################################
+
+sub http_daemon {
+	my $server = IO::Socket::INET->new(
+		Proto => 'tcp',
+		LocalHost => '127.0.0.1',
+		LocalPort => port(8081),
+		Listen => 5,
+		Reuse => 1
+	)
+		or die "Can't create listening socket: $!\n";
+
+	local $SIG{PIPE} = 'IGNORE';
+
+	my $count = 0;
+
+	while (my $client = $server->accept()) {
+		$client->autoflush(1);
+
+		my $headers = '';
+		my $uri = '';
+
+		while (<$client>) {
+			$headers .= $_;
+			last if (/^\x0d?\x0a?$/);
+		}
+
+		next if $headers eq '';
+		$count++;
+
+		Test::Nginx::log_core('||', "response, $count");
+		print $client <<EOF;
+HTTP/1.1 204 No content
+Count: $count
+Connection: close
+
+EOF
+
+	} continue {
+		close $client;
+	}
+}
+
+###############################################################################