diff --git a/core/src/main/java/de/ids_mannheim/korap/web/filter/AuthenticationFilter.java b/core/src/main/java/de/ids_mannheim/korap/web/filter/AuthenticationFilter.java
index 0635c78..4d4a17b 100644
--- a/core/src/main/java/de/ids_mannheim/korap/web/filter/AuthenticationFilter.java
+++ b/core/src/main/java/de/ids_mannheim/korap/web/filter/AuthenticationFilter.java
@@ -45,11 +45,11 @@
 
     @Override
     public void filter (ContainerRequestContext request) {
-        String host = request.getHeaderValue(ContainerRequest.HOST);
-        String ua = request.getHeaderValue(ContainerRequest.USER_AGENT);
+        String host = request.getHeaderString(ContainerRequest.HOST);
+        String ua = request.getHeaderString(ContainerRequest.USER_AGENT);
 
         String authorization =
-                request.getHeaderValue(ContainerRequest.AUTHORIZATION);
+                request.getHeaderString(ContainerRequest.AUTHORIZATION);
 
         if (authorization != null && !authorization.isEmpty()) {
             TokenContext context = null;
diff --git a/core/src/main/java/de/ids_mannheim/korap/web/filter/DemoFilter.java b/core/src/main/java/de/ids_mannheim/korap/web/filter/DemoFilter.java
index 97aa875..e020a8d 100644
--- a/core/src/main/java/de/ids_mannheim/korap/web/filter/DemoFilter.java
+++ b/core/src/main/java/de/ids_mannheim/korap/web/filter/DemoFilter.java
@@ -24,7 +24,7 @@
     @Override
     public void filter (ContainerRequestContext request) {
         String authentication =
-                request.getHeaderValue(ContainerRequest.AUTHORIZATION);
+                request.getHeaderString(ContainerRequest.AUTHORIZATION);
         if (authentication == null || authentication.isEmpty()) {
             if (request.getSecurityContext() == null) {
                 request.setSecurityContext(createContext());
diff --git a/core/src/main/java/de/ids_mannheim/korap/web/filter/DemoUserFilter.java b/core/src/main/java/de/ids_mannheim/korap/web/filter/DemoUserFilter.java
index b34d4b7..f24f957 100644
--- a/core/src/main/java/de/ids_mannheim/korap/web/filter/DemoUserFilter.java
+++ b/core/src/main/java/de/ids_mannheim/korap/web/filter/DemoUserFilter.java
@@ -37,10 +37,10 @@
 
     @Override
     public void filter (ContainerRequestContext request) {
-        String host = request.getHeaderValue(ContainerRequest.HOST);
-        String ua = request.getHeaderValue(ContainerRequest.USER_AGENT);
+        String host = request.getHeaderString(ContainerRequest.HOST);
+        String ua = request.getHeaderString(ContainerRequest.USER_AGENT);
         String authentication = request
-                .getHeaderValue(ContainerRequest.AUTHORIZATION);
+                .getHeaderString(ContainerRequest.AUTHORIZATION);
 
         // means that this is the public service
         if (authentication == null || authentication.isEmpty()) {
diff --git a/core/src/main/java/de/ids_mannheim/korap/web/filter/PiwikFilter.java b/core/src/main/java/de/ids_mannheim/korap/web/filter/PiwikFilter.java
index 6ed86b2..84d27eb 100644
--- a/core/src/main/java/de/ids_mannheim/korap/web/filter/PiwikFilter.java
+++ b/core/src/main/java/de/ids_mannheim/korap/web/filter/PiwikFilter.java
@@ -79,14 +79,14 @@
                     .queryParam("rec", "1")
                     //todo check for empty container
                     .queryParam("_cvar", translateCustomData())
-                    .queryParam("cip", request.getHeaderValue("Host"))
+                    .queryParam("cip", request.getHeaderString("Host"))
                     .queryParam("cookie", "false")
                     .queryParam("r", String.valueOf(random.nextDouble()))
                     .queryParam("action_name",
                             request.getUriInfo().getRequestUri().toASCIIString())
                     .accept("text/html")
-                    .header("Host", request.getHeaderValue("Host"))
-                    .header("User-Agent", request.getHeaderValue("User-Agent"))
+                    .header("Host", request.getHeaderString("Host"))
+                    .header("User-Agent", request.getHeaderString("User-Agent"))
                     .acceptLanguage(l).method("GET");
         }
         catch (Exception e) {