Mr. Ramky,
What "sbctsublc" is not correct. If you read on Sheela Murthy's website care fully, it says, whenever you get extension of H1 or transfer H1 from one employer to other, you must file for your dependents extension/transfer. H4 is not employer specific but it depends on the H1. If H1 changes your H4 should also reflect the change.
Believe me, I have done this 4 times (2 times extension and 2 times transfer) and I have had extended sessions on this topic with lawyer everytime I did it.
Hope it helps.
mhsoor