document ms compiler problems with placement delete

src/ca/comBuf.cpp

@@ -133,8 +133,13 @@ void comBuf::throwInsufficentBytesException ()
 void comBuf::operator delete ( void *pCadaver ) 
     throw ( std::logic_error )
 {
-    throw std::logic_error 
-        ( "compiler is confused about placement delete" );
+    // Visual C++ .net appears to require operator delete if
+    // placement operator delete is defined? I smell a ms rat
+    // because if I declare placement new and delete, but
+    // comment out the placement delete definition there are
+    // no undefined symbols.
+    errlogPrintf ( "%s:%d this compiler is confused about placement delete - memory was probably leaked",
+        __FILE__, __LINE__ );
 }
 
 comBufMemoryManager::~comBufMemoryManager () {}