diff --git a/pwd_stub.go b/pwd_stub.go
index 62c3ab7..d204940 100644
--- a/pwd_stub.go
+++ b/pwd_stub.go
@@ -3,6 +3,9 @@
 package zenity
 
 func password(opts options) (string, string, error) {
+	if opts.username {
+		return "", "", ErrUnsupported
+	}
 	opts.hideText = true
 	str, err := entry("Password:", opts)
 	return "", str, err