Problem adding tax to shipping

I am attempting to add shipping as a taxable-flat rate item but the cart is not adding tax to shipping.

My rule setup in the eCart object for shipping is:
Triggers = Total number of items > 0
Calculation = Flat rate (with a dollar amount of $10.00)

On the main shipping tab I have checked "Include shipping in cart subtotal when calculating sales tax"

When the shopping cart displays, the tax is calculated properly for the items ordered but there is no tax added for shipping.

What did I miss? Is there anything else I can provide that would help?

how is the tax rule configured?

Can you send a link where I can see the problem and a copy of the cart object file in the WA_eCart folder

tax configuration is one rule:
Triggers = Total number of items > 0
Calculation = Based on the cart subtotal
Cart subtotal times 0.10

I am setting up and testing on my local server so I can't give you a link. I have attached the file eCart1_PHP.php from the WA_eCart folder (this appears to be the cart object file).

Let me know if there's anything else I can do.

in the calculation section for the tax rule, you selected to use the Cart Subtotal, you need to select the carts Taxable total to have the shipping included.

that is the solution... thank you!