Help needed: H4 effective date

My wife's H1 expired on July 1st. She filed change of status to H4 on June 27th. Now she received the H4 approval notice, but the H4 is valid from 10/05/07 (approval date). This leaves a three-month gap between H1 and H4. Is this a serious issue that need to be corrected? Your suggestion will be greatly appreciated!