diff --git a/lib/tls b/lib/tls
index 65c2cba..3f59d5b 100644
--- a/lib/tls
+++ b/lib/tls
@@ -485,6 +485,8 @@
     local f_port=$3
     local b_host=$4
     local b_port=$5
+    # 8190 is the default apache size.
+    local f_header_size=${6:-8190}
 
     tune_apache_connections
 
@@ -512,6 +514,11 @@
     # ('Connection aborted.', BadStatusLine("''",)) error
     KeepAlive Off
 
+    # This increase in allowed request header sizes is required
+    # for swift functional testing to work with tls enabled. It is 2 bytes
+    # larger than the apache default of 8190.
+    LimitRequestFieldSize $f_header_size
+
     <Location />
         ProxyPass http://$b_host:$b_port/ retry=0 nocanon
         ProxyPassReverse http://$b_host:$b_port/