diff --git a/scim-wnn/src/romkan.cpp b/scim-wnn/src/romkan.cpp
index 36aa55b..6e3282f 100644
--- a/scim-wnn/src/romkan.cpp
+++ b/scim-wnn/src/romkan.cpp
@@ -245,3 +245,19 @@
 {
     convKataHira(text);
 }
+
+
+/*!
+    \fn Romkan::keyEventHook(const KeyEvent &key)
+ */
+bool Romkan::keyEventHook(const KeyEvent &key)
+{
+    if (text.empty()) return(false);
+    if (text.substr(pos - 1,1) == utf8_mbstowcs("Z")) {
+        if (key.code == SCIM_KEY_space) {
+            insert(key.get_ascii_code());
+            return(true);
+        }
+    }
+    return(false);
+}
diff --git a/scim-wnn/src/romkan.h b/scim-wnn/src/romkan.h
index 649d4be..ca3d54e 100644
--- a/scim-wnn/src/romkan.h
+++ b/scim-wnn/src/romkan.h
@@ -24,6 +24,7 @@
 #include <vector>
 #include <scim.h>
 #include <scim_iconv.h>
+#include <scim_event.h>
 
 using namespace std;
 using namespace scim;
@@ -50,6 +51,7 @@
     void convKataHira(WideString &t);
     void hiraKata();
     void kataHira();
+    bool keyEventHook(const KeyEvent &key);
 
 protected:
     WideString text;
diff --git a/scim-wnn/src/scim_wnn_imengine.cpp b/scim-wnn/src/scim_wnn_imengine.cpp
index 909942d..b749408 100644
--- a/scim-wnn/src/scim_wnn_imengine.cpp
+++ b/scim-wnn/src/scim_wnn_imengine.cpp
@@ -276,6 +276,12 @@
  */
 bool WnnInstance::process_preedit_key_event(const KeyEvent &key)
 {
+    if (m_rk.keyEventHook(key)) {
+        show_preedit_string();
+        update_preedit_string(m_rk.getText());
+        update_preedit_caret(m_rk.getPos());
+        return(true);
+    } else
     if (k_conversion_start.comp(key)) {
         if (!m_rk.getTextLength()) {
             return(false);