Older versions of gnats, up to and including version 3.x, stored
user passwords in plaintext in the gnatsd.user_access files. Version 4
has the options of storing the password as MD5 or standard DES
crypt() hashes (as most UNIX versions do in the system password
files) as well as in plaintext. Since the password strings require a
prefix to indicate how they are encrypted, one is forced to convert the
old password files to a new format when upgrading to gnats version
4. See Upgrading from older versions.
The gnats-pwconv tool takes care of converting the old password
files to the new format:
gnats-pwconv [ -c | --crypt ] [ -m | --md5 ] [ -p | --plaintext ]
[ -h | --help] [ -V | --version ] INFILE [OUTFILE]
Unless the --version or --help options are given, exactly
one encryption method must be specified, as well as an input file. The
output file parameter is optional. If one is not specified, results will
be printed on standard output.