Having problems posting classifieds

I assume you're talking about the "National Classifieds"?

There's the odd glitch in the system that needs to be worked out at times. I've been moderating it for months now and still see problems pop up from time to time. As UM stated, please copy the error for us to determine exactly what the problem is.
Fatal error: Allowed memory size of 8388608 bytes exhausted (tried to allocate 4096 bytes) in /home/class/public_html/image-inc.php on line 137

It worked the first time with no pics, uploaded pics and thats the message it gave me, all are under 200kb