diff --git a/src/nsJohabProber.cpp b/src/nsJohabProber.cpp
index 379a9c3..b5d2321 100644
--- a/src/nsJohabProber.cpp
+++ b/src/nsJohabProber.cpp
@@ -45,7 +45,9 @@ void  nsJohabProber::Reset(void)
   //mContextAnalyser.Reset();
 }
 
-nsProbingState nsJohabProber::HandleData(const char* aBuf, PRUint32 aLen)
+nsProbingState nsJohabProber::HandleData(const char* aBuf, PRUint32 aLen,
+                                         int** cpBuffer,
+                                         int*  cpBufferIdx)
 {
   PRUint32 codingState;
 
@@ -74,7 +76,7 @@ nsProbingState nsJohabProber::HandleData(const char* aBuf, PRUint32 aLen)
   mLastChar[0] = aBuf[aLen-1];
 
   if (mState == eDetecting)
-    if (mDistributionAnalyser.GotEnoughData() && GetConfidence() > SHORTCUT_THRESHOLD)
+    if (mDistributionAnalyser.GotEnoughData() && GetConfidence(0) > SHORTCUT_THRESHOLD)
       mState = eFoundIt;
 //    else
 //      mDistributionAnalyser.HandleData(aBuf, aLen);
@@ -82,7 +84,7 @@ nsProbingState nsJohabProber::HandleData(const char* aBuf, PRUint32 aLen)
   return mState;
 }
 
-float nsJohabProber::GetConfidence(void)
+float nsJohabProber::GetConfidence(int candidate)
 {
   float distribCf = mDistributionAnalyser.GetConfidence();
 
diff --git a/src/nsJohabProber.h b/src/nsJohabProber.h
index e7bc520..02532b3 100644
--- a/src/nsJohabProber.h
+++ b/src/nsJohabProber.h
@@ -50,11 +50,15 @@ public:
     Reset();
   }
   virtual ~nsJohabProber(void){delete mCodingSM;}
-  nsProbingState HandleData(const char* aBuf, PRUint32 aLen);
-  const char* GetCharSetName() {return "Johab";}
+  nsProbingState HandleData(const char* aBuf, PRUint32 aLen,
+                            int** cpBuffer,
+                            int*  cpBufferIdx);
+  int         GetCandidates() {return 1;}
+  const char* GetCharSetName(int) {return "Johab";}
+  const char* GetLanguage(int) {return "ko";}
   nsProbingState GetState(void) {return mState;}
   void      Reset(void);
-  float     GetConfidence(void);
+  float     GetConfidence(int candidate);
   void      SetOpion() {}
 
 protected:
diff --git a/src/nsMBCSGroupProber.cpp b/src/nsMBCSGroupProber.cpp
index dfeb0a8..60db2ce 100644
--- a/src/nsMBCSGroupProber.cpp
+++ b/src/nsMBCSGroupProber.cpp
@@ -304,7 +304,7 @@ nsProbingState nsMBCSGroupProber::HandleData(const char* aBuf, PRUint32 aLen,
 
             for (PRUint32 j = 0; j < NUM_OF_LANGUAGES; j++)
             {
-              float langConf = langDetectors[i][j]->GetConfidence();
+              float langConf = langDetectors[i][j] ? langDetectors[i][j]->GetConfidence() : 1.0;
 
               if (cf * langConf > CANDIDATE_THRESHOLD)
               {
@@ -352,7 +352,7 @@ nsProbingState nsMBCSGroupProber::HandleData(const char* aBuf, PRUint32 aLen,
 
         for (PRUint32 j = 0; j < NUM_OF_LANGUAGES; j++)
         {
-          float langConf = langDetectors[i][j]->GetConfidence();
+          float langConf = langDetectors[i][j] ? langDetectors[i][j]->GetConfidence() : 1.0;
 
           if (cf * langConf > CANDIDATE_THRESHOLD)
           {
diff --git a/test/ko/johab.txt b/test/ko/johab.txt
new file mode 100644
index 0000000..7cf0802
--- /dev/null
+++ b/test/ko/johab.txt
@@ -0,0 +1 @@
+�e�i�e ѩ������ �}���� ���� �����i�i ���� �e�e �q�����a��[1] �e�i �x‘��A��e �}���� 14�� ѩ���� 10 ���� 24�i �a���a�� �q�e�a. "�a�u�i�� ������ �i�a" ���A�i �a�� �A�����׷� �e����e ���� �����a�a �i�a�� �a�a������ 1443�e �w�A�a�a 1446�e �e͡�a�v�a. �{�i�a�a �{�����e �a�a���a�� �q�����a���a �{���� ����, ����, �����i ���� �A�� �e�A ���a�a�� �����A �q�颅�a�� �b���� �x�e�a. ��q�A�e �}���� 17�A ѩ���� 11 ���� 28�����a�a ��A 4�i ���� ���A�e 24�e �e�a. ���e������ ���壥������������������ ���� ���幢 �aá���A��e ���w ���a��, �����A���a ��ɥ ��A��e ���a���a�᷁ ���� ���a�� ��Ȃ�a�v�a. ���壥�����������������A��e ����i(�X�h�i)���a ���e�a.