diff --git a/distrho/src/DistrhoPluginVST3.cpp b/distrho/src/DistrhoPluginVST3.cpp
index 7993163a1..eff8bb11e 100644
--- a/distrho/src/DistrhoPluginVST3.cpp
+++ b/distrho/src/DistrhoPluginVST3.cpp
@@ -310,9 +310,9 @@ ScopedUTF16String::ScopedUTF16String(const char* const s) noexcept
     : str(nullptr)
 {
     const size_t len = strlen(s);
-    str = (int16_t*)malloc(sizeof(int16_t) * len);
+    str = (int16_t*)malloc(sizeof(int16_t) * (len + 1));
     DISTRHO_SAFE_ASSERT_RETURN(str != nullptr,);
-    strncpy_utf16(str, s, len);
+    strncpy_utf16(str, s, len + 1);
 }
 
 ScopedUTF16String::~ScopedUTF16String() noexcept
@@ -1836,26 +1836,42 @@ class PluginVst3
 # if DISTRHO_PLUGIN_WANT_STATE
         if (std::strcmp(msgid, "state-set") == 0)
         {
-            int16_t* key16;
-            int16_t* value16;
-            uint32_t keySize, valueSize;
+            int64_t keyLength = -1;
+            int64_t valueLength = -1;
             v3_result res;
 
-            res = v3_cpp_obj(attrs)->get_binary(attrs, "key", (const void**)&key16, &keySize);
+            res = v3_cpp_obj(attrs)->get_int(attrs, "key:length", &keyLength);
             DISTRHO_SAFE_ASSERT_INT_RETURN(res == V3_OK, res, res);
+            DISTRHO_SAFE_ASSERT_INT_RETURN(keyLength >= 0, keyLength, V3_INTERNAL_ERR);
 
-            res = v3_cpp_obj(attrs)->get_binary(attrs, "value", (const void**)&value16, &valueSize);
+            res = v3_cpp_obj(attrs)->get_int(attrs, "value:length", &valueLength);
+            DISTRHO_SAFE_ASSERT_INT_RETURN(res == V3_OK, res, res);
+            DISTRHO_SAFE_ASSERT_INT_RETURN(valueLength >= 0, valueLength, V3_INTERNAL_ERR);
+
+            int16_t* const key16 = (int16_t*)std::malloc(sizeof(int16_t)*(keyLength + 1));
+            DISTRHO_SAFE_ASSERT_RETURN(key16 != nullptr, V3_NOMEM);
+
+            int16_t* const value16 = (int16_t*)std::malloc(sizeof(int16_t)*(valueLength + 1));
+            DISTRHO_SAFE_ASSERT_RETURN(value16 != nullptr, V3_NOMEM);
+
+            res = v3_cpp_obj(attrs)->get_string(attrs, "key", key16, sizeof(int16_t)*keyLength);
+            DISTRHO_SAFE_ASSERT_INT_RETURN(res == V3_OK, res, res);
+
+            res = v3_cpp_obj(attrs)->get_string(attrs, "value", value16, sizeof(int16_t)*valueLength);
             DISTRHO_SAFE_ASSERT_INT_RETURN(res == V3_OK, res, res);
 
             // do cheap inline conversion
             char* const key = (char*)key16;
             char* const value = (char*)value16;
 
-            for (uint32_t i=0; i<keySize/sizeof(int16_t); ++i)
+            for (int64_t i=0; i<keyLength; ++i)
                 key[i] = key16[i];
-            for (uint32_t i=0; i<valueSize/sizeof(int16_t); ++i)
+            for (int64_t i=0; i<valueLength; ++i)
                 value[i] = value16[i];
 
+            key[keyLength] = '\0';
+            value[valueLength] = '\0';
+
             fPlugin.setState(key, value);
 
             // save this key as needed
@@ -1868,6 +1884,8 @@ class PluginVst3
                     if (dkey == key)
                     {
                         it->second = value;
+                        std::free(key16);
+                        std::free(value16);
                         return V3_OK;
                     }
                 }
@@ -1875,6 +1893,8 @@ class PluginVst3
                 d_stderr("Failed to find plugin state with key \"%s\"", key);
             }
 
+            std::free(key16);
+            std::free(value16);
             return V3_OK;
         }
 # endif
@@ -2043,6 +2063,8 @@ class PluginVst3
         DISTRHO_SAFE_ASSERT_RETURN(attrlist != nullptr,);
 
         v3_cpp_obj(attrlist)->set_int(attrlist, "__dpf_msg_target__", 2);
+        v3_cpp_obj(attrlist)->set_int(attrlist, "key:length", std::strlen(key));
+        v3_cpp_obj(attrlist)->set_int(attrlist, "value:length", std::strlen(value));
         v3_cpp_obj(attrlist)->set_string(attrlist, "key", ScopedUTF16String(key));
         v3_cpp_obj(attrlist)->set_string(attrlist, "value", ScopedUTF16String(value));
         v3_cpp_obj(fConnection)->notify(fConnection, message);
diff --git a/distrho/src/DistrhoUIVST3.cpp b/distrho/src/DistrhoUIVST3.cpp
index 0bd6ce0c1..d50bb203a 100644
--- a/distrho/src/DistrhoUIVST3.cpp
+++ b/distrho/src/DistrhoUIVST3.cpp
@@ -299,27 +299,46 @@ class UIVst3
 #if DISTRHO_PLUGIN_WANT_STATE
         if (std::strcmp(msgid, "state-set") == 0)
         {
-            int16_t* key16;
-            int16_t* value16;
-            uint32_t keySize, valueSize;
+            int64_t keyLength = -1;
+            int64_t valueLength = -1;
             v3_result res;
 
-            res = v3_cpp_obj(attrs)->get_binary(attrs, "key", (const void**)&key16, &keySize);
+            res = v3_cpp_obj(attrs)->get_int(attrs, "key:length", &keyLength);
             DISTRHO_SAFE_ASSERT_INT_RETURN(res == V3_OK, res, res);
+            DISTRHO_SAFE_ASSERT_INT_RETURN(keyLength >= 0, keyLength, V3_INTERNAL_ERR);
 
-            res = v3_cpp_obj(attrs)->get_binary(attrs, "value", (const void**)&value16, &valueSize);
+            res = v3_cpp_obj(attrs)->get_int(attrs, "value:length", &valueLength);
+            DISTRHO_SAFE_ASSERT_INT_RETURN(res == V3_OK, res, res);
+            DISTRHO_SAFE_ASSERT_INT_RETURN(valueLength >= 0, valueLength, V3_INTERNAL_ERR);
+
+            int16_t* const key16 = (int16_t*)std::malloc(sizeof(int16_t)*(keyLength + 1));
+            DISTRHO_SAFE_ASSERT_RETURN(key16 != nullptr, V3_NOMEM);
+
+            int16_t* const value16 = (int16_t*)std::malloc(sizeof(int16_t)*(valueLength + 1));
+            DISTRHO_SAFE_ASSERT_RETURN(value16 != nullptr, V3_NOMEM);
+
+            res = v3_cpp_obj(attrs)->get_string(attrs, "key", key16, sizeof(int16_t)*keyLength);
+            DISTRHO_SAFE_ASSERT_INT_RETURN(res == V3_OK, res, res);
+
+            res = v3_cpp_obj(attrs)->get_string(attrs, "value", value16, sizeof(int16_t)*valueLength);
             DISTRHO_SAFE_ASSERT_INT_RETURN(res == V3_OK, res, res);
 
             // do cheap inline conversion
             char* const key = (char*)key16;
             char* const value = (char*)value16;
 
-            for (uint32_t i=0; i<keySize/sizeof(int16_t); ++i)
+            for (int64_t i=0; i<keyLength; ++i)
                 key[i] = key16[i];
-            for (uint32_t i=0; i<valueSize/sizeof(int16_t); ++i)
+            for (int64_t i=0; i<valueLength; ++i)
                 value[i] = value16[i];
 
+            key[keyLength] = '\0';
+            value[valueLength] = '\0';
+
             fUI.stateChanged(key, value);
+
+            std::free(key16);
+            std::free(value16);
             return V3_OK;
         }
 #endif
@@ -549,6 +568,8 @@ class UIVst3
         DISTRHO_SAFE_ASSERT_RETURN(attrlist != nullptr,);
 
         v3_cpp_obj(attrlist)->set_int(attrlist, "__dpf_msg_target__", 1);
+        v3_cpp_obj(attrlist)->set_int(attrlist, "key:length", std::strlen(key));
+        v3_cpp_obj(attrlist)->set_int(attrlist, "value:length", std::strlen(value));
         v3_cpp_obj(attrlist)->set_string(attrlist, "key", ScopedUTF16String(key));
         v3_cpp_obj(attrlist)->set_string(attrlist, "value", ScopedUTF16String(value));
         v3_cpp_obj(fConnection)->notify(fConnection, message);