If the path to source or pdf file contains an umlaut forward search does not work.
Steps to reproduce:
Create directory with umlaut (example "Lösung")
Create tex file
Compile with "pdflatex --synctex=1"
Forward search from either editor or displayline
File is opened but line neither highlighted nor shown with red dot
Red dot should appear on the line that was given to displayline
Skim 1.4.2 (76)
Mac OS X 10.8.2
resulting synctex file is encoded with utf-8