diff --git a/mozilla/string/public/nsAFlatString.h b/mozilla/string/public/nsAFlatString.h
index bf58c69ae0f..c197bbf32ed 100644
--- a/mozilla/string/public/nsAFlatString.h
+++ b/mozilla/string/public/nsAFlatString.h
@@ -35,11 +35,11 @@ class NS_COM nsAFlatString
   {
     public:
         // don't really want this to be virtual, and won't after |obsolete_nsString| is really dead
-      virtual const PRUnichar* get() const      { return GetBufferHandle()->DataStart(); }
+      virtual const PRUnichar* get() const;
       PRUnichar  operator[]( PRUint32 i ) const { return get()[ i ]; }
       PRUnichar  CharAt( PRUint32 ) const;
 
-      virtual PRUint32 Length() const           { return PRUint32(GetBufferHandle()->DataLength()); }
+      virtual PRUint32 Length() const;
 
 //  protected:  // can't hide these (yet), since I call them from forwarding routines in |nsPromiseFlatString|
     public:
@@ -52,11 +52,11 @@ class NS_COM nsAFlatCString
   {
     public:
         // don't really want this to be virtual, and won't after |obsolete_nsCString| is really dead
-      virtual const char* get() const           { return GetBufferHandle()->DataStart(); }
+      virtual const char* get() const;
       char  operator[]( PRUint32 i ) const      { return get()[ i ]; }
       char  CharAt( PRUint32 ) const;
 
-      virtual PRUint32 Length() const           { return PRUint32(GetBufferHandle()->DataLength()); }
+      virtual PRUint32 Length() const;
 
 //  protected:  // can't hide these (yet), since I call them from forwarding routines in |nsPromiseFlatCString|
     public:
diff --git a/mozilla/string/src/nsAFlatString.cpp b/mozilla/string/src/nsAFlatString.cpp
index 143f2c419f5..114d01ad1b2 100644
--- a/mozilla/string/src/nsAFlatString.cpp
+++ b/mozilla/string/src/nsAFlatString.cpp
@@ -114,3 +114,33 @@ nsAFlatCString::GetWritableFragment( nsWritableFragment<char>& aFragment, nsFrag
           return 0;
       }
   }
+
+PRUint32
+nsAFlatString::Length() const
+  {
+    const nsBufferHandle<PRUnichar>* handle = GetBufferHandle();
+    return PRUint32(handle ? handle->DataLength() : 0); 
+  }
+
+PRUint32
+nsAFlatCString::Length() const
+  {
+    const nsBufferHandle<char>* handle = GetBufferHandle();
+    return PRUint32(handle ? handle->DataLength() : 0); 
+  }
+
+const PRUnichar* 
+nsAFlatString::get() const
+  { 
+    const nsBufferHandle<PRUnichar>* handle = GetBufferHandle();
+    NS_ASSERTION(handle, "handle is null!");
+    return handle ? handle->DataStart() : 0; 
+  }
+
+const char* 
+nsAFlatCString::get() const
+  { 
+    const nsBufferHandle<char>* handle = GetBufferHandle();
+    NS_ASSERTION(handle, "handle is null!");
+    return handle ? handle->DataStart() : 0; 
+  }
diff --git a/mozilla/xpcom/string/public/nsAFlatString.h b/mozilla/xpcom/string/public/nsAFlatString.h
index bf58c69ae0f..c197bbf32ed 100644
--- a/mozilla/xpcom/string/public/nsAFlatString.h
+++ b/mozilla/xpcom/string/public/nsAFlatString.h
@@ -35,11 +35,11 @@ class NS_COM nsAFlatString
   {
     public:
         // don't really want this to be virtual, and won't after |obsolete_nsString| is really dead
-      virtual const PRUnichar* get() const      { return GetBufferHandle()->DataStart(); }
+      virtual const PRUnichar* get() const;
       PRUnichar  operator[]( PRUint32 i ) const { return get()[ i ]; }
       PRUnichar  CharAt( PRUint32 ) const;
 
-      virtual PRUint32 Length() const           { return PRUint32(GetBufferHandle()->DataLength()); }
+      virtual PRUint32 Length() const;
 
 //  protected:  // can't hide these (yet), since I call them from forwarding routines in |nsPromiseFlatString|
     public:
@@ -52,11 +52,11 @@ class NS_COM nsAFlatCString
   {
     public:
         // don't really want this to be virtual, and won't after |obsolete_nsCString| is really dead
-      virtual const char* get() const           { return GetBufferHandle()->DataStart(); }
+      virtual const char* get() const;
       char  operator[]( PRUint32 i ) const      { return get()[ i ]; }
       char  CharAt( PRUint32 ) const;
 
-      virtual PRUint32 Length() const           { return PRUint32(GetBufferHandle()->DataLength()); }
+      virtual PRUint32 Length() const;
 
 //  protected:  // can't hide these (yet), since I call them from forwarding routines in |nsPromiseFlatCString|
     public:
diff --git a/mozilla/xpcom/string/src/nsAFlatString.cpp b/mozilla/xpcom/string/src/nsAFlatString.cpp
index 143f2c419f5..114d01ad1b2 100644
--- a/mozilla/xpcom/string/src/nsAFlatString.cpp
+++ b/mozilla/xpcom/string/src/nsAFlatString.cpp
@@ -114,3 +114,33 @@ nsAFlatCString::GetWritableFragment( nsWritableFragment<char>& aFragment, nsFrag
           return 0;
       }
   }
+
+PRUint32
+nsAFlatString::Length() const
+  {
+    const nsBufferHandle<PRUnichar>* handle = GetBufferHandle();
+    return PRUint32(handle ? handle->DataLength() : 0); 
+  }
+
+PRUint32
+nsAFlatCString::Length() const
+  {
+    const nsBufferHandle<char>* handle = GetBufferHandle();
+    return PRUint32(handle ? handle->DataLength() : 0); 
+  }
+
+const PRUnichar* 
+nsAFlatString::get() const
+  { 
+    const nsBufferHandle<PRUnichar>* handle = GetBufferHandle();
+    NS_ASSERTION(handle, "handle is null!");
+    return handle ? handle->DataStart() : 0; 
+  }
+
+const char* 
+nsAFlatCString::get() const
+  { 
+    const nsBufferHandle<char>* handle = GetBufferHandle();
+    NS_ASSERTION(handle, "handle is null!");
+    return handle ? handle->DataStart() : 0; 
+  }