diff --git a/jeeutil/src/main/java/de/muehlencord/shared/jeeutil/restexfw/APIErrorResponse.java b/jeeutil/src/main/java/de/muehlencord/shared/jeeutil/restexfw/APIErrorResponse.java
index b063af5..ee7d4fd 100644
--- a/jeeutil/src/main/java/de/muehlencord/shared/jeeutil/restexfw/APIErrorResponse.java
+++ b/jeeutil/src/main/java/de/muehlencord/shared/jeeutil/restexfw/APIErrorResponse.java
@@ -37,7 +37,7 @@ public class APIErrorResponse {
     private final Response.Status status;
     private final String errorCode;
     private final String message;
-    private final Throwable rootCause;
+    private final String rootCause;
 
     public APIErrorResponse(APIError apiError, Locale locale) {
         this.status = apiError.getStatus();
@@ -50,7 +50,7 @@ public class APIErrorResponse {
         this.status = apiError.getStatus();
         this.errorCode = apiError.getErrorCode();
         this.message = getLocalizedMessage(apiError, locale);
-        this.rootCause = th;
+        this.rootCause = th.getMessage();
     }
 
     public APIErrorResponse(Exception exception, Locale locale) {
@@ -64,7 +64,7 @@ public class APIErrorResponse {
         this.status = Response.Status.INTERNAL_SERVER_ERROR;
         this.errorCode = "0";
         this.message = exception.getLocalizedMessage();
-        this.rootCause = th;
+        this.rootCause = th.getMessage();
     }
 
     public APIErrorResponse(Response.Status status, String errorCode, String messageKey, Locale locale) {
@@ -86,7 +86,7 @@ public class APIErrorResponse {
         return this.message;
     }
 
-    public Throwable getRootCause() {
+    public String getRootCause() {
         return rootCause;
     }
 
diff --git a/jeeutil/src/main/java/de/muehlencord/shared/jeeutil/restexfw/APIException.java b/jeeutil/src/main/java/de/muehlencord/shared/jeeutil/restexfw/APIException.java
index 3f30358..e122237 100644
--- a/jeeutil/src/main/java/de/muehlencord/shared/jeeutil/restexfw/APIException.java
+++ b/jeeutil/src/main/java/de/muehlencord/shared/jeeutil/restexfw/APIException.java
@@ -54,7 +54,7 @@ public class APIException extends RuntimeException {
                 .header(HTTP_HEADER_X_ERROR_CODE, response.getErrorCode());
         
         if (response.getRootCause() != null) {
-            builder = builder.header(HTTP_HEADER_X_ROOT_CAUSE, builder);
+            builder = builder.header(HTTP_HEADER_X_ROOT_CAUSE, response.getRootCause()); 
         }
 
         return builder.build();