Change Employeer while H1B Transfer in process

[KiranYarra]

Hi All

I have H1B approval from a consultancy in US and that H1 was not stamped. I797 expired in Nov-2011 and my current employer filed for transfer and exempt on previous H1B approval and i got EACXXX receipt number to track my application.

Now if i want to change employer in US is it possible? If yes, employer can be changed on already applied H1B extension or do i need to wait for current H1B approval and after that do i need to change?

Please help me otherwise i will lose one good opportunity.

Kiran