[Not a ZC bug] Problems using '3 AND 4' comments during checkout

[linuxguy2]

Existing installation & Fresh OUT OF THE BOX install.
Buy and item and at step "Step 1 of 3 - Delivery Information" in the "Special Instructions or Comments About Your Order" box enter any 2 numeric values with an "and" or "or" between them, click continue "Check Out" and you get this catastrophic failure.

Forbidden
You don't have permission to access /zctest/index.php on this server.
Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.

EXAMPLE entries:
3 and 4
7 or 9

You may test at this site:
www.pcsnnets.com/zctest



Thanks, Linuxguy2