So we did some testing today, and surprisingly i never thought that zen cart would have such old known bug.
If you create an account and you use letters like ä ö å æ ø for Scandinavian country's the account is going to be made with the tags but all your settings like address, name, last name and so on is totally wiped.
This also counts for trying to update the addresses after with the letters i took a screenshot to show you what i mean, This is with ALL information added on registration page on the left side of the picture and and trying to update with letters after on right side of the picture.
Found out that you actually can update to the correct names via the admin interface, but as a customer/user you will have a hard time trying to figure out what the h3ll is going on, not even to talk about, customer registrations could look like fake/scams, since they technically could write an adress like Horse Road 1 Æ Horse Road 2 but only the text from behind Æ would be picked up for registration so outcome would be
when in fact it should
HTML Code:
Horse Road 1 Æ Horse Road 2