wrong tax calculation during checkout

All my product prices are inclusive tax. Tax is applied to all countrys within the EU. During checkout if you set your country within the EU, the total price does not increase and the tax is showing as a line item.

If the customer choose a country outside the EU, the tax line disappears.

So far so good but now the problem is the total price stays the same but it supposed to be without the tax.

For example:
I have a item in my store for lets say 100 € inclusive 19% tax. I live inside the EU so on checkout the tax line says 16 € and the total price is 100 €. Everything is right.

However if I choose a country outside the EU the tax line disappears but the total price is still 100€. It supposed to be 84 €.

Any help?

Thanks,

https://wordpress.org/plugins/wp-e-commerce/