diff --git a/scim-wnn/src/wnnconversion.cpp b/scim-wnn/src/wnnconversion.cpp
index 08bea82..37b04a2 100644
--- a/scim-wnn/src/wnnconversion.cpp
+++ b/scim-wnn/src/wnnconversion.cpp
@@ -89,8 +89,7 @@
 {
     wnn = jl_open((char *)name.data(),(char *)host.data(),(char *)rc.data(),wnn_error,wnn_message,timeout);
     //wnn = jl_open_lang("test","localhost","jp_JP","/usr/lib/wnn7/ja_JP/wnnenvrc",wnn_error,wnn_message,10);
-    if (wnn == NULL) return(false);
-    return(true);
+    return(isConnected());
 }
 
 
@@ -100,7 +99,7 @@
 void WnnConversion::wnnDisconnect()
 {
     reset();
-    if (wnn) jl_close(wnn);
+    if (isConnected()) jl_close(wnn);
     wnn = 0;
 }
 
@@ -110,7 +109,7 @@
  */
 bool WnnConversion::isConnected()
 {
-    if (wnn) return(true);
+    if (wnn != NULL) return(true);
     else (false);
 }