Wrong indentation because of pdfmark?

Hi!

Why does the following produce an indentation on "Line 1" with Lout 3.36
and Ghostscript 8.63? If I omit the whole "@BackEnd @Case" stuff,
there's no indentation as it should be.
***
@SysInclude { doc }
@Doc @Text @Begin
@BackEnd @Case {
    PostScript @Yield {
        {
            [ "/"Author "("author")"
              "/"Title "("title")"
              "/"Subject "("subject")"
              "/"Keywords "("keywords")"
              "/"DOCINFO pdfmark
        } @Graphic {}
    }
}
Line 1 @LLP
Line 2
@End @Text
***

Robert Riebisch
-- 
BTTR Software
http://www.bttr-software.de/