I used to work for company A till Feb 2010. Currently I have my visa stamped with company A’s name- valid till Sept 2011.
I got laid off in Feb 2010 from company A – applied for change of status to F1 to maintain status
Got another job in 40 days of so – USCIS approved my F1 and H1 petitions simultaneously and in that order.So now I am with company B – with an approved H1 and I 797 for company B and visa stamp with company A

I am visiting my home country in Dec 2010
My question is – Do I have to get my visa stamped? (because of change of status incidences?)Or Is combination of a stamped visa and valid I797 good enough for entry without any hassle at the port of entry irrespective of change of status incidences mentioned above?

Thank you for your time

SG