Is it a common problem for you? Because if it's only once and a while it's probably normal. Sometimes people just poop their pants, ya know? Especially if you are in a situation where you can't get to a bathroom quickly.
Is it IBS? No, hmmm...most of the people I know with bowel issues have issues with going, not keeping from, so I dunno. I'd try something that slows the process down, but nothing immediately comes to mind that would help with that.
