jquery mobile & php define variable
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I'm really new with jQuery mobile but am loving working with it!
I've come across a few problems regarding caching that I'm struggling with though. Hopefully, someone can help me!

I have a php file with the following define in it:

define('HEADING_TITLE', 'Page 1');

That file is loaded on page 1 of the website. When I echo HEADING_TITLE, I see 'Page 1'.

Page 2 requires a different php file that overrides HEADING_TITLE as follows:

define('HEADING_TITLE', 'Page 2');

When I echo HEADING_TITLE, I still see 'Page 1'.
I know the page 2 define is being processed because if I add the line 'die(HEADING_TITLE);' immediately after the define, the script does indeed die but still shows me 'Page 1'!

How do I get jQuery mobile to allow me to overwrite the HEADING_TITLE variable?
Or will I need to go about this another way?
Creating different define variables like PAGE1_HEADING_TITLE and PAGE2_HEADING_TITLE is no problem, but if there's a better way I'd love to know it.

Thanks guys!