Adding the fixed file only.
This is a quick&dirty fix that is described in
http://forums.oscommerce.com/topic/2.../page__st__360 , post 393 and 394.
And everybody else that gets "Notice: Undefined variable: "

I don't know the real reason for it - it seems like the function should not be called when it does - or at least get the variables right.
This is not a good repair, I barely program PHP - it's only a dirty fix.

I hope the authors will look into the reason for this problem and fix it properly..

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