Normaly, First* & Last* you must type your first name & last name. But with this TIPS, you must not
HERE'S HOW ... ↓↓↓
Step1: Connect to http://edit.yahoo.com/config/edit_account and type your ID, Password
Step2: Holt ALT button and type 255: ALT 255 (on keyboard)
Step3: Press "Finished" button to save.
Note: Sometimes, you can use "ALT+32", it's similar to "ALT+255"
Test it immediately, I think Yahoo & Other services will Fix this "TIPS" !