Incompatibility between GnuPG 1.2 and 1.4?

[Christian Stork]

Hi,

A friend of mine uses Enigmail to encrypt his mail on a SuSE 9.x box
with gpg 1.2.1 installed.
Since I upgraded my Debian box to use gpg 1.4.1 I can't decrypt his
mails anymore:

    $gpg-1.4.1 mal1.asc

    You need a passphrase to unlock the secret key for
    user: "Christian H. Stork (University) <cstork at ics.uci.edu>"
    3072-bit ELG-E key, ID B0BE33B2, created 1999-10-02 (main key ID 50F9CA2F)

    gpg: encrypted with 2048-bit ELG-E key, ID 4A12AF6D, created 2001-12-14
          "Marc-Andre Lemburg <mal at lemburg.com>"
    gpg: encrypted with 3072-bit ELG-E key, ID B0BE33B2, created 1999-10-02
          "Christian H. Stork (University) <cstork at ics.uci.edu>"
    gpg: uncompressing failed: unknown compress algorithm
    gpg: WARNING: message was not integrity protected

But it works with gpg 1.2:

    $gpg-1.2.4 mal1.asc 
    You need a passphrase to unlock the secret key for
    user: "Christian H. Stork (University) <cstork at ics.uci.edu>"
    3072-bit ELG-E key, ID B0BE33B2, created 1999-10-02 (main key ID 50F9CA2F)

    gpg: encrypted with 2048-bit ELG-E key, ID 4A12AF6D, created 2001-12-14
          "Marc-Andre Lemburg <mal at lemburg.com>"
    gpg: encrypted with 3072-bit ELG-E key, ID B0BE33B2, created 1999-10-02
          "Christian H. Stork (University) <cstork at ics.uci.edu>"
    gpg: old style (PGP 2.x) signature
    gpg: Signature made Mon Sep 19 12:28:25 2005 PDT using DSA key ID 6A6DDB60
    gpg: Good signature from "Marc-Andre Lemburg <mal at lemburg.com>"
    gpg:                 aka "Marc-Andre Lemburg <mal at egenix.com>"
    gpg: WARNING: message was not integrity protected

Here's part of his gpg.conf:

---------------8<-------------------------------

# Needed for PGP 5.x interop
compress-algo 1
cipher-algo CAST5
no-sk-comments
s2k-cipher-algo CAST5
s2k-digest-algo SHA1
rfc1991

# The next option is enabled because this one is needed for interoperation
# with PGP 5 users.  To enable full OpenPGP compliance you have to remove
# this option.
force-v3-sigs

# Because some mailers change lines starting with "From " to ">From "
# it is good to handle such lines in a special way when creating
# cleartext signatures; all other PGP versions do it this way too.
# To enable full OpenPGP compliance you have to remove this option.
escape-from-lines

----------------8<---------------------------------

Do I need to invoke gpg 1.4 with special options (I tried several
combinations without success)?

I'd be happy to provide more details if that is needed.

Thanks for your time,
Chris

-- 
Chris Stork   <>  Support eff.org!  <>   http://www.ics.uci.edu/~cstork/
OpenPGP fingerprint:  B08B 602C C806 C492 D069  021E 41F3 8C8D 50F9 CA2F