Hi Alan. I've answered this in your email, but will repeat it here for brevity. I thought I had posted about this somewhere back when it was discovered, but can find no record of it.
"This is a known issue with 10.6. ZenEdit shows a prompt when it is launched stating in effect to not worry about it. There is a checkbox on that warning to 'not show again'. At some point you must have checked that if you're not seeing it.
Nothing to worry about, and the problem goes away in newer versions of OSX."