diff --git a/src/bank-lib/bank_twisted.conf b/src/bank-lib/bank_twisted.conf
index ab006b913..71bcaee00 100644
--- a/src/bank-lib/bank_twisted.conf
+++ b/src/bank-lib/bank_twisted.conf
@@ -2,6 +2,7 @@
 [twister]
 # HTTP listen port for twister
 HTTP_PORT = 8888
+SERVE = tcp
 
 # HTTP Destination for twister.  The test-Webserver needs
 # to listen on the port used here.  Note: no trailing '/'!
diff --git a/src/lib/test_exchange_api_twisted.conf b/src/lib/test_exchange_api_twisted.conf
index ba59b5a60..bb06fee86 100644
--- a/src/lib/test_exchange_api_twisted.conf
+++ b/src/lib/test_exchange_api_twisted.conf
@@ -4,6 +4,7 @@
 [twister]
 # HTTP listen port for twister
 HTTP_PORT = 8888
+SERVE = tcp
 
 # HTTP Destination for twister.  The test-Webserver needs
 # to listen on the port used here.  Note: no trailing '/'!