Can't enter some letters for Custom Shepard's name?

One of my characters in the OG Mass Effect was an Adept named Héloïse Shepard. I'd like to play the character again in the Legendary Edition, and I know for ME1 that basically means recreating her from scratch, but when I try, I cannot enter the letter "ï" ("i" with a diaeresis/umlaut) into the name field using ASCII code. This worked fine on the original game; is there a workaround for the LE version?