[XeTeX] Odd and confusing diagnostics during XeTeX run

[Philip TAYLOR (Webmaster, Ret'd)]

Dear Colleagues -- I just knocked up this little
six-line XeTeX source file in order to typeset
some labels for my spice jars in "an appropriate
font" :

    \parindent = 0 em
    \parskip = 6 ex
    \font \Hindi = Samarkan at 36 pt
    \Hindi
    CA's Curry Masala
    \end

When I ran it, I saw some diagnostics flash across
the TeXworks screen, but then the expected PDF appeared,
containing the text "CA's Curry Masala" in Samarkan
as intended.

Puzzled, I removed the \end and re-ran it, and this
time managed to trap the diagnostics; they read --

    This is XeTeX, Version 3.1415926-2.2-0.9997.4 (Web2C 2010)
    entering extended mode
    (./Hindi.texname = Samarkan, rootname = Samarkan, pointsize =
    mktexmf: empty or non-existent rootfile!

    kpathsea: Running mktexmf Samarkan.mf

    The command name is E:\TeX\Live\2010\bin\win32\mktexmf
    Cannot find Samarkan.mf.
    )

Now why is XeTeX trying to use MetaFont sources when
I already have Samarkan in in my system fonts directory
as a Truetype font; XeTeX "knows" that I have it there,
because it successfully uses it, so why does it first
try to use a non-existent MetaFont version.  And why
do the diagnostics :

    mktexmf: empty or non-existent rootfile!

    kpathsea: Running mktexmf Samarkan.mf

    The command name is E:\TeX\Live\2010\bin\win32\mktexmf
    Cannot find Samarkan.mf.

not end up in the document log file (and indeed, where
am I meant to find them) ?

Philip Taylor