diff --git a/honoka/src/honoka_imengine.cpp b/honoka/src/honoka_imengine.cpp
index 2d587c6..8f95e84 100644
--- a/honoka/src/honoka_imengine.cpp
+++ b/honoka/src/honoka_imengine.cpp
@@ -377,7 +377,7 @@
  */
 void HonokaInstance::changeConvertor(const String &name)
 {
-    if (m_conversion) return;
+    //if (m_conversion) return;
     for(unsigned int i = 0;i < convertors.size();i ++) {
         if (convertors[i]->getPropertyName() == name) {
             m_convertor = convertors[i];
@@ -766,6 +766,25 @@
         }
         return(true);
     } else
+    if (k_next_convertor.comp(key) || k_prev_convertor.comp(key)) {
+        for(unsigned int i = 0;i < convertors.size();i ++) {
+            if (convertors[i]->getPropertyName() == m_convertor->getPropertyName()) {
+                if (k_next_convertor.comp(key)) {
+                    if (i == (convertors.size() - 1)) i = 0;
+                    else i ++;
+                } else {
+                    if (i == 0) i = convertors.size() - 1;
+                    else i --;
+                }
+                changeConvertor(convertors[i]->getPropertyName());
+                if (m_def_convertor != m_convertor) {
+                    m_def_convertor->reset();
+                    startConversion();
+                }
+                return(true);
+            }
+        }
+    } else 
     if (key.get_ascii_code()) {
         if (key.mask & (SCIM_KEY_AltMask | SCIM_KEY_ControlMask)) return(false);
             if (m_lookup && numkeyselect) {
@@ -1005,6 +1024,9 @@
 void HonokaInstance::startConversion(WideString s)
 {
     // ����lookup�Ͼä��Ƥ�������
+    m_def_convertor = m_convertor;
+    if (!s.length()) s = yomi;
+    else yomi = s;
     m_lookup = false;
     m_lookup_table.clear();
     hide_lookup_table();
diff --git a/honoka/src/honoka_imengine.h b/honoka/src/honoka_imengine.h
index aee97d3..4370d9f 100644
--- a/honoka/src/honoka_imengine.h
+++ b/honoka/src/honoka_imengine.h
@@ -91,6 +91,7 @@
     CommonLookupTable m_lookup_table;
     PreEditor *m_preeditor;
     Convertor *m_convertor;
+    Convertor *m_def_convertor;
     bool m_conversion;
     bool m_yosoku;
     bool m_lookup;
@@ -107,11 +108,12 @@
     vector<PreEditor *> preeditors;
     vector<Convertor *> convertors;
     String sType;
+    WideString yomi;
 protected:
     bool process_preedit_key_event(const KeyEvent &key);
     bool process_conversion_key_event(const KeyEvent &key);
     bool process_yosoku_key_event(const KeyEvent &key);
-    void startConversion(WideString s);
+    void startConversion(WideString s = WideString());
     void createLookupTable(ResultList cList);
     void init();
     void updatePreEditor();