diff --git a/jams-server/src/main/java/net/jami/jams/server/Server.java b/jams-server/src/main/java/net/jami/jams/server/Server.java
index da45b671db4329763655cf310f96f205e57883a7..582bb165f2da7044a44325765cc4489ebce6a796 100644
--- a/jams-server/src/main/java/net/jami/jams/server/Server.java
+++ b/jams-server/src/main/java/net/jami/jams/server/Server.java
@@ -64,6 +64,7 @@ public class Server {
     public static AppUpdater appUpdater;
 
     public Server(AppUpdater appUpdater, String port, String serverCertificate, String serverPrivateKey) {
+        ClassPool.getDefault().clearImportedPackages();
         JsoniterRegistry.initCodecs();
         Server.appUpdater = appUpdater;
         String[] args = {port, serverCertificate, serverPrivateKey};
diff --git a/jams-server/src/main/java/net/jami/jams/server/core/workflows/InstallationFinalizer.java b/jams-server/src/main/java/net/jami/jams/server/core/workflows/InstallationFinalizer.java
index a4b4f16d1a9e1489481a903c045db5305d05dcdb..40068f3349f90e94dec5d048d1149725a81bba27 100644
--- a/jams-server/src/main/java/net/jami/jams/server/core/workflows/InstallationFinalizer.java
+++ b/jams-server/src/main/java/net/jami/jams/server/core/workflows/InstallationFinalizer.java
@@ -23,6 +23,7 @@
 package net.jami.jams.server.core.workflows;
 
 import com.jsoniter.output.JsonStream;
+import javassist.ClassPool;
 import lombok.extern.slf4j.Slf4j;
 import net.jami.jams.common.authentication.AuthenticationSourceType;
 import net.jami.jams.common.objects.roots.X509Fields;