diff --git a/include/wx/colourdata.h b/include/wx/colourdata.h
index dfaab13f26..d05a9a37b4 100644
--- a/include/wx/colourdata.h
+++ b/include/wx/colourdata.h
@@ -26,6 +26,8 @@ public:
 
     void SetChooseFull(bool flag) { m_chooseFull = flag; }
     bool GetChooseFull() const { return m_chooseFull; }
+    void SetChooseAlpha(bool flag) { m_chooseAlpha = flag; }
+    bool GetChooseAlpha() const { return m_chooseAlpha; }
     void SetColour(const wxColour& colour) { m_dataColour = colour; }
     const wxColour& GetColour() const { return m_dataColour; }
     wxColour& GetColour() { return m_dataColour; }
@@ -45,6 +47,9 @@ public:
     wxColour        m_custColours[NUM_CUSTOM];
     bool            m_chooseFull;
 
+protected:
+    bool            m_chooseAlpha;
+
     wxDECLARE_DYNAMIC_CLASS(wxColourData);
 };
 
diff --git a/src/common/colourdata.cpp b/src/common/colourdata.cpp
index 1748076863..3ad774195f 100644
--- a/src/common/colourdata.cpp
+++ b/src/common/colourdata.cpp
@@ -25,6 +25,7 @@ wxIMPLEMENT_DYNAMIC_CLASS(wxColourData, wxObject);
 wxColourData::wxColourData()
 {
     m_chooseFull = false;
+    m_chooseAlpha = false;
     m_dataColour.Set(0,0,0);
     // m_custColours are wxNullColours initially
 }
@@ -61,6 +62,7 @@ wxColourData& wxColourData::operator=(const wxColourData& data)
 
     m_dataColour = data.m_dataColour;
     m_chooseFull = data.m_chooseFull;
+    m_chooseAlpha = data.m_chooseAlpha;
 
     return *this;
 }
@@ -85,6 +87,9 @@ wxString wxColourData::ToString() const
             str += clr.GetAsString(wxC2S_HTML_SYNTAX);
     }
 
+    str.Append(wxCOL_DATA_SEP);
+    str.Append(m_chooseAlpha ? '1' : '0');
+
     return str;
 }
 
@@ -102,6 +107,14 @@ bool wxColourData::FromString(const wxString& str)
         else
             success = m_custColours[i].Set(token);
     }
+
+    if ( success )
+    {
+        token = tokenizer.GetNextToken();
+        m_chooseAlpha = token == wxS("1");
+        success = m_chooseAlpha || token == wxS("0");
+    }
+
     return success;
 }