Office 2003 Clipboard runs out of space. How to increase buffer size?

I read that the space available for clipboard collections is dependent upon the amount of available system memory.

However, when I perform screen captures via CTL+Prt Scrn or Print Screen alone, the clipboard fills up after only a couple of screen shots. And a message is generated – “Item not collected: Delete items to increase available space.”

So, I was wondering if there is a known hack (running Windows XP), or a place to modify it’s memory usage configuration?