KeyError: 'ulVersion' - how can I fix it?

[Adrian]

Penultimate line of run code shows 'KeyError'. Can anyone say why this would happen?
Thanks...

Last login: Sat Nov 11 11:47:38 on ttys002
Adrians-iMac:~ adrianshome$ which ttx
/Users/adrianshome/bin/FDK/Tools/osx/ttx
Adrians-iMac:~ adrianshome$ FLDR="${HOME}/Desktop/Dsig fldr"
Adrians-iMac:~ adrianshome$ mkdir -p "$FLDR"
Adrians-iMac:~ adrianshome$ cd "$FLDR"
Adrians-iMac:Dsig fldr adrianshome$ cat > dsig.ttx<<EOF
> <?xml version="1.0" encoding="ISO-8859-1"?>
> <ttFont sfntVersion="\x00\x01\x00\x00" ttLibVersion="2.4">
> <DSIG>
> <hexdata>
> 00000001 00000000
> </hexdata>
> </DSIG>
> </ttFont>
> EOF
Adrians-iMac:Dsig fldr adrianshome$ open .
Adrians-iMac:Dsig fldr adrianshome$ /Applications/FDK/Tools/osx/ttx -m /Users/adrianshome/Desktop/Dsig\ fldr/SassoonSansUSLine.ttf /Users/adrianshome/Desktop/Dsig\ fldr/dsig.ttx
Compiling "/Users/adrianshome/Desktop/Dsig fldr/dsig.ttx" to "/Users/adrianshome/Desktop/Dsig fldr/dsig.ttf"...
Parsing 'DSIG' table...
Traceback (most recent call last):
File "/Applications/FDK/Tools/osx/../SharedData/FDKScripts/ttx.py", line 329, in <module>
main(sys.argv[1:])
File "/Applications/FDK/Tools/osx/../SharedData/FDKScripts/ttx.py", line 309, in main
process(jobs, options)
File "/Applications/FDK/Tools/osx/../SharedData/FDKScripts/ttx.py", line 294, in process
action(input, output, options)
File "/Applications/FDK/Tools/osx/../SharedData/FDKScripts/ttx.py", line 216, in ttCompile
ttf.save(output)
File "/Applications/FDK/Tools/osx/Python/Current/lib/python2.7/site-packages/FontTools/fontTools/ttLib/__init__.py", line 214, in save
self._writeTable(tag, writer, done)
File "/Applications/FDK/Tools/osx/Python/Current/lib/python2.7/site-packages/FontTools/fontTools/ttLib/__init__.py", line 629, in _writeTable
tabledata = self.getTableData(tag)
File "/Applications/FDK/Tools/osx/Python/Current/lib/python2.7/site-packages/FontTools/fontTools/ttLib/__init__.py", line 642, in getTableData
return self.tables[tag].compile(self)
File "/Applications/FDK/Tools/osx/Python/Current/lib/python2.7/site-packages/FontTools/fontTools/ttLib/tables/D_S_I_G_.py", line 60, in compile
packed = sstruct.pack(DSIG_HeaderFormat, self)
File "/Applications/FDK/Tools/osx/Python/Current/lib/python2.7/site-packages/FontTools/fontTools/misc/sstruct.py", line 68, in pack
value = obj[name]
KeyError: 'ulVersion'
Adrians-iMac:Dsig fldr adrianshome$