Build Output window behaviour with DOS batch file


My build process involves uVision running a DOS batch file to perform various operations prior to compilation.  The batch file contains various "echo" statements to indicate progress.  However, these do not appear in the Build Output window until after the batch file has completed.  I would like them to appear as and when they are encountered in the batch file.  It seems that output is buffered up by uVision and flushed to the Build Output window at the end. Is there a way to change this behaviour?