PHP Warning mktime() expects parameter 6 to be long

Hi everyone,

I'm just trying to help a client figure out why his Zen Cart /cache/myDEBUG-xxxxxxx.log files show this over and over:

PHP Warning: mktime() expects parameter 6 to be long, string given in /home/****/public_html/cart/includes/functions/functions_general.php on line 1476

I checked line 1476 in functions_general.php and it simply holds this:

$date1_set = mktime(0,0,0, $m1, $d1, $y1);

I've searched the ZC FAQ area as well as this forum and I can't seem to find any explanation or anyone with the same problem.

Since I'm not the cart owner and I'm just trying to help, I don't have a ton of details but I do know the following information:

ZC Version - 1.39d
Environment - Redhat Enterprise Linux, Apache 2.2, PHP 5.13, mySQL 5.1.47

The store has been live and handling transactions without issues for a long time.

I'll try to get more details from him ASAP, but I was hoping that in the meantime perhaps someone here has already experienced this kind of issue and knows what needs to be changed.

Thank you kindly for any help at all!

A very important piece of information is what was being attempted when the error was produced.
That function is called from all kinds of possible places, so it's impossible to just pick one out of the air and guess which other page or addon or customization is calling that function with bad data.

Thanks DrByte. I'll schedule a call with him and have him run through some test transactions while I watch the apache logs and the debug logs to see if we can nail it down.