How thin is the oil are you using, or how old.  Or did you recently have to crank and crank to get the engine to start?  That floods gas into the engine oil and thins it out.  Always change oil after that happens.  If it is thin, it thinks there isn't enough pressure.  Sythetic oil can do it too on an older engine.  If you use the cheap oil filters they say that happens too.
Dave

--- On Tue, 2/8/11, Paul <wognacious@GMAIL.COM> wrote:

> From: Paul <wognacious@GMAIL.COM>
> Subject: Oil light flickering
> To: vanagon@GERRY.VANAGON.COM
> Date: Tuesday, February 8, 2011, 8:25 AM
> Lately at low idle my oil light has
> been flickering. Rev up the RPM's and it
> goes away. I have plenty of oil, you know the usual 1/2
> full on the dip
> stick. Should I be replacing the oil pressure sensor's?
> Anybody else have
> this happen?
> TIA,
> Paul
>