Emacs mode-line-format

[Timothy M. Schaeffer]

I am running Emacs 20.3.1 (i386-suse-linux) under (of all things) SuSe
Linux, kernel 2.2.10.  I have line-number-mode set to true.  It does not,
however, show the line number, but only two question marks ("??") where the
line number should be.  I couldn't find in the sources where the mode line
is
drawn, so I have no clue why this is happening.  It is very
annoying.  setnu.el is a temporary workaround, but has its problems.
Anyone?  TIA - Tim S.

mode-line-format =>

("-" mode-line-mule-info
     mode-line-modified
     mode-line-frame-identification
     mode-line-buffer-identification
     "   "
     global-mode-string
     "   %[(" mode-name
              mode-line-process minor-mode-alist "%n"
     ")%]--"
     (which-func-mode ("" which-func-format "--"))
     (line-number-mode "L%L--")
     (column-number-mode "C%c--")
     (-3 . "%p") "-%-")