You need to quote the string again. The shell that reads the command breaks it up on spaces unless properly quoted.

Try an extra set of quotes for DOS/Win or backslashes for *Nix.

...roboticus

Update: Try executing that exact command line in a standard DOS shell and see what happens... ;^)

This would work in DOS/Win:

C:\> "C:\Program Files\yadda yadda\foo.exe" argWithNoSpace "Arg with a
+ space"
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For *Nix it depends on your shell. I use bash:

$ /DOS/C/Program\ Files/yadda\ yadda/foo.exe argWithNoSpaces Arg\ with
+\ a\ space
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