Making Asset Purchases with different currencies

Currently, it is only possible to make an "Asset Purchase" transaction using the same currency from the payments account. If you want to add to an asset account with a different currency (let's say USD) than the one you use for your payments account (let's say EUR), you have to create a dummy payments account in USD in this case, transfer funds from the payments account in EUR to the payments account in USD and then make the asset purchase in USD.