apt-0.3.x on slink: unable to parse package file

Hello Debian folks,

anybody out there who can help me with apt being "unable to parse package file":

I am trying to use apt-0.3.x for a series of slink CDs I wrote at the office
in order to install slink on my private PC at home. For the two official
slink CDs, everything works fine: first "apt-cdrom add", then "dselect" with
access method apt, then update package descriptions and so on...

I have written a third CD containing my download of the slink "non-US" directory
structure, for which I can also do "apt-cdrom add" without any errors.
But after adding this CD to the sources list, the update of package descriptions out of dselect gives me the following error:

--- snip ---
Reading Package Lists... Error!
E: Unable to parse package file
/var/state/apt/lists/nonus_dists_slink_non-US_binary-i386_Packages (1)
E: The package lists or status file could not be parsed or opened.

update available list script returned error exit status 100.
Press RETURN to continue.
--- snip ---

The package file with this lenghty name:
/var/state/apt/lists/nonus_dists_slink_non-US_binary-i386_Packages

does exist, and - as far as I can tell - does not look any different from the
other package files apt-cdrom created for the official CDs.

I have attached the original package file on which apt complains (33653 bytes) to this mail, so please can anybody look at it and tell me if it really is corrupted?
If not, what else can be wrong when trying to parse this file?

I started using apt-0.3.5 with slink, but even upgrading to libc6-2.1,
libstdc++2.9-glibc2.1 and apt-0.3.6 (using standalone dpkg) did not solve the problem :-(

Thanks in advance for any help,

Andreas
a.loew@pop3.main-kinzig.net