In version 1.4, searching for 

(^.*JAVA_OPTS=.*-Dprogram.name.*?)(\")?$

and replacing with 

$1 -Dap.home=c:/dir$2

Will return a string with 'null' on the end if the optional " character is not
matched.

So the line

set JAVA_OPTS=%JAVA_OPTS% -Dprogram.name=%PROGNAME%

will incorrectly become 

set JAVA_OPTS=%JAVA_OPTS% -Dprogram.name=%PROGNAME% -Dap.home=c:/dirnull

But 

set JAVA_OPTS="%JAVA_OPTS% -Dprogram.name=%PROGNAME%"

will correctly become

set JAVA_OPTS="%JAVA_OPTS% -Dprogram.name=%PROGNAME% -Dap.home=c:/dir"