Zencart 1.3.7 compatible with PHP 5?

I am currently running:

PHP Version: 4.4.9 (Zend: 1.3.0)
Zen Cart 1.3.7
Database Patch Level: 1.3.7

I would like to upgrade my PHP to version 5. I am worried if there will be issues in doing so? Can someone please confirm if this is ok or if I should expect to encounter issues?

Thanks!

http://www.zen-cart.com/forum/showthread.php?t=140960

Note that the patch is for 1.3.8, but DrByte has offered edits for your version.

Obviously, the best solution would be to upgrade to 1.3.9d.

I'd love to upgrade to the latest version... but I'm affraid all my mods, add-ons, and custom shop skin will get messed up. Since I had to hire someone to create it all for me and don't have the tech know=how to do the upgrade seamlessly myself I'm afraid I'm stuck.

No money to pay someone to upgrade my site and the original skin developer is nowhere to be found. :(

Sometimes I wish Zencart was as easy as Wordpress was to upgrade and DIY it.

You need to figure out upgrading - your version is vulnerable to several security exploits.