Doctrine: How to mark object column value as dirty?

[TheDruid]

I have a column of type object in a model. But if I load a model, and change a property of the object, and then re-save, it doesn't seem re-serialize the object. e.g.\[code\]$model_instance = $table->find(1);$object = $model_instance->object_column;$object->someProp = 'new value';$model_instance->save(); //has no effect\[/code\]I think this is because it is checking for modification by comparing the old and new values using \[code\]!==\[/code\], which returns false because they are both references to the same object. I could clone the object before saving but there clearly must be a more obvious way which I have missed.