diff --git a/t/mail/gateway.t b/t/mail/gateway.t
index c51daa90925..8f9e941c40a 100644
--- a/t/mail/gateway.t
+++ b/t/mail/gateway.t
@@ -2,7 +2,7 @@ use strict;
 use warnings;
 
 
-use RT::Test config => 'Set( @MailPlugins, "Action::Take", "Action::Resolve");', tests => undef, actual_server => 1;
+use RT::Test config => 'Set( @MailPlugins, "Action::Take", "Action::Resolve"); Set($DevelMode, 1);', tests => undef, actual_server => 1;
 my ($baseurl, $m) = RT::Test->started_ok;
 
 use RT::Tickets;
diff --git a/t/mail/han-encodings.t b/t/mail/han-encodings.t
index ba1acc0cd45..d2dc5238022 100644
--- a/t/mail/han-encodings.t
+++ b/t/mail/han-encodings.t
@@ -1,7 +1,7 @@
 use strict;
 use warnings;
 
-use RT::Test tests => undef, actual_server => 1;
+use RT::Test tests => undef, config => 'Set($DevelMode, 1);', actual_server => 1;
 
 # we can't simply call Encode::HanExtra->require here because we are testing
 # if Encode::HanExtra could be automatically loaded.
diff --git a/t/ticket/interface.t b/t/ticket/interface.t
index fd3ee581bbd..71013d16973 100644
--- a/t/ticket/interface.t
+++ b/t/ticket/interface.t
@@ -1,7 +1,7 @@
 use strict;
 use warnings;
 
-use RT::Test tests => undef, actual_server => 1;
+use RT::Test tests => undef, config => 'Set($DevelMode, 1);', actual_server => 1;
 
 my ( $baseurl, $m ) = RT::Test->started_ok;