I'm attaching a LaTeX file and the resulting PDF (from MacTeX2008).
The problem is that the text: [tʰ] should not be [th], nor [mʲ] like [mj], or [kʷ] like [kw]. gets treated (copy-and-pasted, screen-read) by the PDF viewers as: [th] should not be [th], nor [mj] like [mj], or [kw] like [kw].The Unicode character for IPA diacritic ʰ shouldn't be treated as ASCII h in superscript any more than Cyrillic н should be treated as ASCII h in small caps.
After more poking around, the problem seems to be in the PDF viewers and I'd guess that XeLaTeX has put the right Unicode characters into the file. Mac Preview claims to find two instances of "[th]" while also claiming to find one instance of "[tʰ]", though it fails to highlight it. Adobe Reader claims to find two instances of both "[th]" and "[tʰ]", but highlights apparently at random. Skim finds only "[th]". All three viewers act the same way for a PDF file (using Gentium) exported from OpenOffice.
-- Kevin Russell
superscript.tex
Description: TeX document
superscript.pdf
Description: Adobe PDF document
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