Acacia doesn't help me with my C, it only gives me a buffer to be able to eat things...
If you are desperate you can always take a strong laxative (dulcolax for example, its OTC), it feels bad, but it works. That's what I usually do when I haven't gone for a week.
Massage might help, too. My aunt (who is a lifelong C sufferer, I think she might have IBS too) said it helped her to massage the belly in a clockwise direction (you know, the colon starts at your right, goes up, goes left, goes down, so in that direction).