diff --git a/src/gen_cpp_Engine.ysl2 b/src/gen_cpp_Engine.ysl2
index 4ffe80b..614dd16 100644
--- a/src/gen_cpp_Engine.ysl2
+++ b/src/gen_cpp_Engine.ysl2
@@ -8,17 +8,21 @@ tstylesheet {
     template "interface" document("org_pEp_jniadapter_{@name}.cc", "text")
         ||
         #include <assert.h>
+        #include <pEp/message_api.h>
         #include "org_pEp_jniadapter_«@name».h"
         #include "jniutils.hh"
 
         using namespace pEp::JNIAdapter;
 
+        extern "C" {
+
         `` apply "method", 0
+        } // extern "C"
+
         ||
 
     template "method" {
         const "mangled" call "mangle";
-        const "jtype" call "CamelCase" with "text", "name(parm[creates|returns]/*[2])";
 
         ||
         JNIEXPORT jobject JNICALL «$mangled»(
@@ -26,13 +30,26 @@ tstylesheet {
                 jobject obj`apply "parm[in]", mode=sig`
             )
         {
+            PEP_SESSION session = (PEP_SESSION) callLongMethod(env, obj, "getHandle");
+
+            `` apply "parm[in]", mode=in
+            `` apply "parm[creates|returns]", mode=out
+
+            PEP_STATUS status = ::«@name»(session`apply "parm", mode=call``if "@name = 'encrypt_message'" > , PEP_enc_PEP`);
+
         ||
 
         choose {
             when "count(parm[returns|creates]) > 1"
-                |> jclass clazz = findClass(env, "org/pEp/jniadapter/_«@name»_Return");
+                ||
+                    jclass clazz = findClass(env, "org/pEp/jniadapter/_«@name»_Return");
+                ||
+
             when "count(parm[returns|creates]) = 1" {
-                |> jclass clazz = findClass(env, "org/pEp/jniadapter/«$jtype»");
+                const "jtype" call "CamelCase" with "text", "name(parm[creates|returns]/*[2])";
+                ||
+                    jclass clazz = findClass(env, "org/pEp/jniadapter/«$jtype»");
+                ||
             }
         }
 
@@ -47,6 +64,39 @@ tstylesheet {
         ||
     }
 
+    template "parm", mode=in {
+        const "type", "name(*[2])";
+        const "name", "name(*[3])";
+
+        choose {
+            when "$type = 'message'"
+                | message *_«$name» = (message *) callLongMethod(env, «$name», "getHandle");
+            otherwise
+                | √$type *_«$name» = to_«$type»(env, «$name»);
+        }
+    }
+
+    template "parm", mode=out {
+        const "type", "name(*[2])";
+        const "name", "name(*[3])";
+
+        choose {
+            when "$type = 'Color'"
+                | PEP_color _«$name»;
+            otherwise
+                | √$type *_«$name»;
+        }
+    }
+
+    template "parm", mode=call {
+        const "dir", "name(*[1])";
+        const "name", "name(*[3])";
+     
+        > , 
+        if "$dir = 'creates' or $dir = 'returns'" > &
+        > _«$name»
+    }
+
     function "mangle" {
         const "convert", "count(parm/stringlist|parm/string|parm/identity) > 0";
 
diff --git a/src/gen_java_Engine.ysl2 b/src/gen_java_Engine.ysl2
index 02d1eff..80e6821 100644
--- a/src/gen_java_Engine.ysl2
+++ b/src/gen_java_Engine.ysl2
@@ -140,9 +140,11 @@ tstylesheet {
         const "type", "name(*[2])";
         const "name" call "lcase" with "text", "name(*[3])";
 
-        if "$dir = 'in'" {
-            if "$type = 'string' or $type = 'stringlist'" | ¡$type _«$name» = AbstractEngine.toUTF8(«$name»);
-            if "$type = 'identity'" | _Identity _«$name» = new _Identity(«$name»);
+        if "$dir = 'in'" choose {
+            when "$type = 'string' or $type = 'stringlist'"
+                | ¡$type _«$name» = AbstractEngine.toUTF8(«$name»);
+            when "$type = 'identity'"
+                | _Identity _«$name» = new _Identity(«$name»);
         }
     }
 
@@ -152,9 +154,12 @@ tstylesheet {
         const "name" call "lcase" with "text", "name(*[3])";
 
         if "$dir != 'in'" choose {
-            when "$type = 'string' or $type = 'stringlist'" | result.«$name» = AbstractEngine.toUTF16(_result.«$name»);
-            if "$type = 'identity'" | result.«$name» = Identity(«$name»);
-            otherwise | result.«$name» = _result.«$name»;
+            when "$type = 'string' or $type = 'stringlist'"
+                | result.«$name» = AbstractEngine.toUTF16(_result.«$name»);
+            when "$type = 'identity'"
+                | result.«$name» = Identity(«$name»);
+            otherwise
+                | result.«$name» = _result.«$name»;
         }
     }
 
@@ -162,7 +167,8 @@ tstylesheet {
         const "type", "name(*[2])";
         const "name" call "lcase" with "text", "name(*[3])";
 
-        if "$type = 'string' or $type = 'stringlist'" > _
+        if "$type = 'string' or $type = 'stringlist' or $type = 'identity'"
+            > _
         > «$name»`if "position()!=last()" > , `
     }
 }
diff --git a/src/jniutils.cc b/src/jniutils.cc
index 5e06379..49abb8b 100644
--- a/src/jniutils.cc
+++ b/src/jniutils.cc
@@ -328,9 +328,13 @@ namespace pEp {
             pEp_identity *ident = new_identity(NULL, NULL, NULL, NULL);
 
             ident->address = _getStringField(env, classname, obj, "address");
+            ident->address_size = strlen(ident->address);
             ident->fpr = _getStringField(env, classname, obj, "fpr");
+            ident->fpr_size = strlen(ident->fpr);
             ident->user_id = _getStringField(env, classname, obj, "user_id");
+            ident->user_id_size = strlen(ident->user_id);
             ident->username = _getStringField(env, classname, obj, "username");
+            ident->username_size = strlen(ident->username);
 
             jfieldID comm_type_id = getFieldID(env, classname, "comm_type", "I");
             ident->comm_type = (PEP_comm_type) (int) env->GetIntField(obj, comm_type_id);