strange behaviour of \definedfont['Some Name'] in XeTeX

["Mojca Miklavec" <mojca.miklavec.lists@gmail.com>]

Hello,

I'm probaby misusing the feature (most robably because I just didn't
take time to study how to do it properly), but it behaves really
strange.

In XeTeX I first did

\font\f='Some Name' \f

which worked OK. But when I tried the same with
     \definedfont['Some Name']
it resulted in strange behaviour. For some fonts, metapost has been
invoked and complained, but the resulting document had the proper font
plus "scaled 1000" written on the first page where the font has been
selected. For other fonts it failed completely.

What's actually the most clean way of including an "uc-encoded" font
at a specific font size, but without the need of bold or any other
"typefaces" (just for a title for example)? (Which basically means: I
only want the same behaviour as the plain TeX expression above + uc
encoding.)

Thanks,
    Mojca