--- a/lib/python/signing/utils.py
+++ b/lib/python/signing/utils.py
@@ -243,26 +243,26 @@ def jar_unsignfile(filename):
     # it returns with 12 if it has nothing to do
     if proc.wait() not in (0, 12):
         stdout.seek(0)
         data = stdout.read()
         log.error("zip output: %s", data)
         raise ValueError("Couldn't remove previous signature")
 
 
-def jar_signfile(filename, keystore, keyname, fake=False, passphrase=None):
+def jar_signfile(filename, keystore, keyname, digestalg, sigalg, fake=False, passphrase=None):
     """Sign a jar file
     """
     # unsign first
     jar_unsignfile(filename)
     command = [
         "jarsigner",
         "-keystore", keystore,
-        "-digestalg", "SHA1",
-        "-sigalg", "SHA1withDSA",
+        "-digestalg", digestalg,
+        "-sigalg", sigalg,
         filename
     ]
     if keyname:
         command.append(keyname)
     stdout = tempfile.TemporaryFile()
     try:
         log.debug("running %s", command)
         proc = Popen(command, stdout=stdout, stderr=STDOUT, stdin=PIPE)

--- a/release/signing/signscript.py
+++ b/release/signing/signscript.py
@@ -25,16 +25,18 @@ if __name__ == '__main__':
         gpg_homedir=None,
         loglevel=logging.INFO,
         configfile=None,
         mar_cmd=None,
         mar_sha384_cmd=None,
         signcode_timestamp=None,
         jar_keystore=None,
         jar_keyname=None,
+        jar_sigalg=None,
+        jar_digestalg=None,
         emevoucher_key=None,
         emevoucher_chain=None,
     )
     parser.add_option("--keydir", dest="signcode_keydir",
                       help="where MozAuthenticode.spc, MozAuthenticode.spk can be found")
     parser.add_option("--gpgdir", dest="gpg_homedir",
                       help="where the gpg keyrings are")
     parser.add_option("--mac_id", dest="mac_id",
@@ -46,16 +48,20 @@ if __name__ == '__main__':
     parser.add_option("-c", "--config", dest="configfile",
                       help="config file to use")
     parser.add_option("--signcode_disable_timestamp",
                       dest="signcode_timestamp", action="store_false")
     parser.add_option("--jar_keystore", dest="jar_keystore",
                       help="keystore for signing jar_")
     parser.add_option("--jar_keyname", dest="jar_keyname",
                       help="which key to use from jar_keystore")
+    parser.add_option("--jar_digestalg", dest="jar_digestalg",
+                      help="which digest algorithm to use for signing jar files")
+    parser.add_option("--jar_sigalg", dest="jar_sigalg",
+                      help="which signature algorithm to use for signing jar files")
     parser.add_option("--emevoucher_key", dest="emevoucher_key",
                       help="The certificate to use for signing the eme voucher")
     parser.add_option("--emevoucher_chain", dest="emevoucher_chain",
                       help="Certificate chain to include in EME voucher signatures")
     parser.add_option(
         "-v", action="store_const", dest="loglevel", const=logging.DEBUG)
 
     options, args = parser.parse_args()
@@ -154,11 +160,13 @@ if __name__ == '__main__':
         dmg_signpackage(inputfile, tmpfile, options.dmg_keychain, options.mac_id, options.mac_cert_subject_ou, options.fake, passphrase)
     elif format_ == "jar":
         if not options.jar_keystore:
             parser.error("jar_keystore required when format is jar")
         if not options.jar_keyname:
             parser.error("jar_keyname required when format is jar")
         copyfile(inputfile, tmpfile)
         jar_signfile(tmpfile, options.jar_keystore,
-                     options.jar_keyname, options.fake, passphrase)
+                     options.jar_keyname,
+                     digestalg=options.jar_digestalg, sigalg=options.jar_sigalg,
+                     options.fake, passphrase)
 
     os.rename(tmpfile, destfile)