[XeTeX] Strange Euler Script font behaviour

[Will Robertson]

Hi

What is going on?

    \font\1=eusm10 at 12 pt\1
    ABCD
    \bye

In pdfTeX, I get "ABCD" in the Euler Script font.
In XeTeX, I get "BCDE" (in Euler Script again) with messed up spacing.

Given such a minimal document (no LaTeX encodings or anything!), I'm 
totally confused what's happening. But that might be my (plain) TeX 
ignorance showing.

Is this a bug? It's quite significant, since euler.sty gets about a 
dozen of its symbols from this font, which render incorrectly 
(including \{ \} | \aleph \Re \Im etc.). Not to mention not being able 
to use the Euler Script font itself.

Regards,
Will

PS Also, I'm surprised this hasn't been noticed before since I 
-thought- people had been using Euler to blend better with other text 
fonts, e.g., Hoefler Text.