Reader does a "save as" instead of a "save" on first save of an enabled form

[Jared_Langdon]

I have a form created using LC Designer and extended using Acrobat (Save As Other --> Reader Extended PDF --> Enable More Tools).

When I enter data using Adobe Reader and File-->Save, it behaves as though I had selected "Save As".  If I want to overwrite the file, it prompts me to confirm.  From then on, when I save it behaves as expected (i.e. it automatically overwrites the file with my changes).  If I close the file and open it again, then make changes, then save, it does a "save as" again. 

I don't want it to handle "save" as a "save as".  Anyone know a way to avoid this behaviour? 

[TomatPremier]

Yes, when I enter data in the form using Reader I am forced to use Save As.  The Save button causes an error message saying the form is either read only or already open. Shouldn't the Save button just save the file?