#7 fast question -- laxatives

I've just started the #7 fast. When I was reading up on that and other fasts (e.g., the master cleanser fast), everything I read said that you absolutely *must* have bowle movements every day during a cleanse because otherwise the toxins stay in your system.

In the #7 fast, if experiencing blockage problems, is it permissable to drink a herbal laxative tea, such as Smooth Move? If not, does anyone else have suggestions, should I run into this problem?

Thanks.