splitting categories.php into 2 files problems with cPath

[alba]

I am trying to spilt the existing categories.php file into 2 seperate files once for the categories functions (category.php) and one to edit the products (product.php) and so far all has gone well apart from one weird issue i just cant put my thumb on...

lets for example say i have a category ID 9 and a products ID 37

 

when i link from category.php to the product edit page: product.php?cPath=9&pID=37&action=new_product i get a very strange issue

 

If i load it as product.php?cPath=9&pID=37&action=new_product the product edit fields all form correctly and the cPath populates the title of the product edit.. example: New Product in "computers > Products" but the actual data from the database for that product doesnt populate

 

I found by accident that if i load it as product.php??cPath=9&pID=37&action=new_product (note the second ?) the product edit fields all form correctly but the cPath doesnt populate the title of the product but the actual data from the database for that product does populate

 

I also find that if i echo $HTTP_GET_VARS['cPath'] on the first example it returns the right category ID number and on the second example it doesnt populate at all

 

to give you an idea of what i have done category.php is an exact replica of categories.php but with the product edit functions removed and the product.php is again a clone of categories.php but with the product preview and category functions removed

 

anyone have any ideas what bizarre thing may cause this?