How to handle expense transactions prior to incorporation date

SUGGESTED

Can the fiscal start date of a new corporation be dated prior to the incorporation date?  I'm a small business bookkeeper for a client who has registered his new company as a corporation as of March 3 but he has expenses dating back to February 4.  I haven't finished entering the history...can I back-date the fiscal start to February 4 so he can claim those expenses?  Sage 50 will let me do that but is it permitted for a corporation to do that?  Thank-you for any advice.