Safari Browser Http Referrer Null

I have tested application I serveral different browser types but I have ran into an issue with the Safari browser. I'm recording information from the Http Referrer on each page load but when I click the back button of Safari the Http Referrer is null which causes an error in my application.

//this code blows up

if( Request.UrlReferrer.tostring != string.empty)

{

//save information

}

Any thoughts or tips so that .net will detect the referrer correctly ?

 

Thanks in advance,

 skobyjay
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