I - 140 approved - Can we switch employer and return ?

[manihs]

I currently have a approved I - 140 - Dec 2008. However I wanted to join another employer for a year or so and return back to my old employer by mid next year. As there are issues finding a project in the short term.

Is this possible ? . Please advise .. Will I risk my current H1 (valid for another 2 years) ...

Pls advise.