Hi, I have a problem with the PdfHandler extension to display thumbnails of PDF files

When uploading a PDF file the thumbnail and pages are not generated giving the following error instead of the image (I've tried different PDFs):

---- Error creating thumbnail: convert: no decode delegate for this image format `/tmp/magick-XXY76lVk'. convert: missing an image filename `/var/www/w/images/thumb/8/84/Poster.pdf/page1-424px-Poster.pdf.jpg'. ----

Some debugging seems to show that Ghostscript may be to blame. If writing the Ghostscript output to a file instead of piping it to convert in the PHP script I get:

---- Unrecoverable error: stackunderflow in .setdistillerparams ----

Issueing the same command from the command line works fine and produces a thumbnail:

---- ('/usr/bin/gs' -sDEVICE=jpeg -sOutputFile=- -dFirstPage=1 -dLastPage=1 -r150 -dBATCH -dNOPAUSE -q '/var/www/w/images/8/84/Poster.pdf' | sudo '/usr/bin/convert' -depth 8 -resize 424 - '/var/www/w/images/thumb/8/84/Poster.pdf/page1-424px-Poster.pdf.jpg') 2>&1 ----

Software: Linux 2.6.26-2-vserver-amd64 gs-gpl 8.62.dfsg.1-3.2lenny1 imagemagick 7:6.3.7.9.dfsg2-1~lenny3 php5-cgi 5.2.6.dfsg.1-1+lenny4

How can I further debug? Hope anyone can help!

matsch