[XeTeX] Fontspec: SizeFeatures don't accept ItalicFont? (Fell types)

[Grzegorz Murzynowski]

Hi everyone,

I'm trying to \fontspec the Fell types provided by Igino Marini at 
www.iginomarini.com
treating them as optical sizes.
I take the TrueType version since there's a bug in Adobe Reader not 
allowing to render the OpenType version correctly.

  So I use the SizeFeature option:

\setmainfont[%
      Ligatures=Rare,
     Scale=MatchLowercase,
     SizeFeatures={
       {Size = -7,   Font=IM FELL English, FakeStretch=1.1,
         FakeBold=1}, % tiny
       {Size = 7-8.5,          Font=IM FELL English, FakeStretch=1.06,
         FakeBold=0.5}, %scriptsize
       {Size = 8.5-10.5,   Font=IM FELL English}, % footnotesize \& small
       {Size = 10.5-11.5, Font=IM FELL DW Pica}, % normalsize (for 11pt 
class option)
       {Size = 11.5-19,    Font=IM FELL Double Pica}, % heading sizes
       {Size = 19-,             Font=IM FELL Great Primer}% huge+ sizes
     }
     ]{IM FELL English}%

But then I don't get Italics, I mean \emph and \textit typeset their 
arguments upright. I'd like to add ItalicFont option but it would have 
to be done also with SizeFeature and I get an obscure error message
	‘SizeFeatures’ not defined in family ‘options’
which seems to suggest that ItalicFeatures doesn't accept SizeFeatures.
I get similar error message when trying add ItalicFont={* Italic} to 
every (any) size features.

What to do? All that should be done is making XeTeX/fontspec to select 
for italics font with the name as upright with ‘Italic’ added (e.g.
	{Size = 10.5-11.5, Font=IM FELL DW Pica, ItalicFont={IM FELL DW Pica 
Italic}}

Any suggestions?

Grzegorz Murzynowski