H4 expired at 1st Nov.07,6th yrs, I-94 shows Feb 21st,07. how to

my wife's H4 expires on Nov 1st, 2007 and her I-94 sheet attached on her passport shows Feb 21, 2007. she still has her h4 I-797 notice form with a new I-94 together that shows Nov. 1st, 2007. the questions are 1, is it necessary for her to correct her I-94 form? 2, my company will expand my H1 and hers H4 for 7th yrs and we should get a new notice with I-94 to show the new date of Nov 1st,2008. we have no plan to travel to china this yrs but in 2008 we might go back to china for some reasons. if it is necessary to correct her I-94, should i make an appointment by infopass and how much does it cost? my local office at San Antonio. she got her I-94 on Aug.17th when she came back from china, thanks.