Spring Webflow - how to store a variable

I have a problem with my dev environment triggering the same On Entry event to a View State twice. (Something to do with UrlReWrite but thats another matter. I think it is going to take ages to work out.)

Would like to do a quick hack in the mean time.

That is, test if the output of the On Entry event (which is currently going into a viewScope variable), has already been set. If so, return it gain, as it has to be the second time through. Make sense?

But how can I set a variable in the On Entry event that is visible the second time through? I tried passing in the viewScope variable that is sets but it is always null. I take it the viewScope variables are not visible inside an On Entry event POJO?

There must be a way, right?

Thanks