Description of problem:
just tried 'sudo dnf update'

Version-Release number of selected component:
dnf-0.4.8-1.fc20

Additional info:
reporter:       libreport-2.1.9
cmdline:        /usr/bin/python /bin/dnf update
executable:     /bin/dnf
kernel:         3.11.10-301.fc20.x86_64
runlevel:       N 5
type:           Python
uid:            0

Truncated backtrace:
miscutils.py:61:checkSig:OSError: [Errno 2] No such file or directory: '/var/cache/dnf/x86_64/20/updates/packages/PackageKit-0.8.14-3.fc20.x86_64.rpm'

Traceback (most recent call last):
  File "/bin/dnf", line 35, in <module>
    main.user_main(sys.argv[1:], exit_code=True)
  File "/usr/lib/python2.7/site-packages/dnf/cli/main.py", line 279, in user_main
    errcode = main(args)
  File "/usr/lib/python2.7/site-packages/dnf/cli/main.py", line 64, in main
    return _main(base, args)
  File "/usr/lib/python2.7/site-packages/dnf/cli/main.py", line 192, in _main
    return_code, resultmsgs = base.do_transaction()
  File "/usr/lib/python2.7/site-packages/dnf/cli/cli.py", line 198, in do_transaction
    if self.gpgsigcheck(downloadpkgs) != 0:
  File "/usr/lib/python2.7/site-packages/dnf/cli/cli.py", line 218, in gpgsigcheck
    result, errmsg = self.sigCheckPkg(po)
  File "/usr/lib/python2.7/site-packages/dnf/base.py", line 1022, in sigCheckPkg
    sigresult = dnf.rpmUtils.miscutils.checkSig(ts, po.localPkg())
  File "/usr/lib/python2.7/site-packages/dnf/rpmUtils/miscutils.py", line 61, in checkSig
    fdno = os.open(package, os.O_RDONLY)
OSError: [Errno 2] No such file or directory: '/var/cache/dnf/x86_64/20/updates/packages/PackageKit-0.8.14-3.fc20.x86_64.rpm'

Local variables in innermost frame:
currentflags: 986880
ts: <dnf.rpmUtils.transaction.TransactionWrapper object at 0x216cd50>
value: 0
package: '/var/cache/dnf/x86_64/20/updates/packages/PackageKit-0.8.14-3.fc20.x86_64.rpm'