diff --git a/include/wx/string.h b/include/wx/string.h
index 6667f8fae8..2ae0085719 100644
--- a/include/wx/string.h
+++ b/include/wx/string.h
@@ -429,9 +429,9 @@ public:
   const_iterator end() const { return m_pchData + length(); }
 
   // first valid index position
-  iterator begin() { CopyBeforeWrite(); return m_pchData; }
+  iterator begin();
   // position one after the last valid one
-  iterator end() { CopyBeforeWrite(); return m_pchData + length(); }
+  iterator end();
 
     // insert another string
   wxStringBase& insert(size_t nPos, const wxStringBase& str)
diff --git a/src/common/string.cpp b/src/common/string.cpp
index 9b1de655cd..70473982fd 100644
--- a/src/common/string.cpp
+++ b/src/common/string.cpp
@@ -407,6 +407,20 @@ bool wxStringBase::Alloc(size_t nLen)
   //else: we've already got enough
   return TRUE;
 }
+  
+wxStringBase::iterator wxStringBase::begin()
+{
+    if (length() > 0)
+        CopyBeforeWrite();
+    return m_pchData;
+}
+
+wxStringBase::iterator wxStringBase::end()
+{
+    if (length() > 0)
+        CopyBeforeWrite();
+    return m_pchData + length();
+}
 
 wxStringBase::iterator wxStringBase::erase(iterator it)
 {