gaim-url-handler defect

XMPP links don't work. When running via terminal, gaim-url-handler outputs the following error messages:

thielmann@diabolus:~ $ gaim-url-handler "xmpp:<email address hidden>?message"
/usr/bin/gaim-url-handler:27: DeprecationWarning: raising a string exception is deprecated
  raise "Error: " + self.attr + " " + str(args) + " returned " + str(result)
Traceback (most recent call last):
  File "/usr/bin/gaim-url-handler", line 285, in <module>
    main()
  File "/usr/bin/gaim-url-handler", line 278, in main
    xmpp(uri)
  File "/usr/bin/gaim-url-handler", line 218, in xmpp
    account = findaccount(protocol, accountname)
  File "/usr/bin/gaim-url-handler", line 51, in findaccount
    account = cgaim.GaimAccountsFindAny(accountname, protocolname)
  File "/usr/bin/gaim-url-handler", line 27, in __call__
    raise "Error: " + self.attr + " " + str(args) + " returned " + str(result)
Error: GaimAccountsFindAny ('<email address hidden>', 'prpl-jabber') returned 0

Any idea on how to solve that problem?