Hi Celelibi,
in case this is still relevant to you (I can't find any trace of this
bug report in my mailbox, I'm sorry you had to wait so long for a first
reply): I think you can achieve what you want by using the command
"xpdf.real" instead of just "xpdf".
/usr/bin/xpdf is a shell script that Debian adds since $forever, mainly
in order to automatically open PDFs compressed with gzip/xz/bzip2 etc.
While shell scripting is often quickly done, it's hard to get right for
every possible use case. The script correctly parses the quoted value
with the space, however it fails to correctly reproduce the space in the
call to the actual binary, /usr/bin/xpdf.real - and I can't seem to come
up with a clean fix that works for all obvious situations, hence tagging
this bug HELP.
Florian