I have H1-B Approved as consular processing from 2009 Cap from employer X.I am working for employer Y on L1-B since 2008 and have not used H1-B from employer Y

I have offer from employer Z with client letter and employer wants me to join in 1 month.

Can i tranfer my approved H1-B from employer X to employer Z that is COS from L1-H1-B with start date of employment as 1 july 2011 based on approved H1 out of 2009 quota to get cap exempt benfit and start working since 1 july

I do not have any pay stubs for H1-B but i have maintained valid L1-B status since 2009 and have L1 pay stubs.