Symbol's function definition is void: cancel-timer with maildir Gcc

[Arcady Genkin]

After upgrade to Xemacs packages SUMO tarball version 2005-03-07 (from
2004-08-18), I am getting the following error message when sending mail
in Gnus (5.10.6 from the said packages tarball):

  Symbol's function definition is void: cancel-timer

I traced it down to the following Gcc header:

  Gcc: nnmaildir:sent-mail-2005-03

If I remove the header, the error goes away.  It also goes away if I
(require 'timer).  Perhaps the timer library is not properly loaded
from some Gnus function (e.g. related to nnmaildir)?