[O] Error message could be improved - Specified time is not representable

[Julian Bean]

Hi all,

On upgrading to emacs 23.3 (from emacs 23.1) my daily/weekly agenda became 
unusable, giving the error message "Specified time is not representable".

After a bit of poking around in the backtrace I tracked this down to an 
erroneous SCHEDULED date of 1st January 1904 buried inside a task. (This date 
was created by a bug in a script I was using to import TODOs from another 
system).

Evidently, for some reason, calling (encode-time 0 0 0 1 1 1904) on 23.3 causes 
the error above, whereas on 23.1 it's silently ignored?

I think the best thing for org-mode is to catch this error and report it to the 
user in a more understandable way so they can locate and fix the buggy 
timestamp - at least, include the full text of the timestamp so they can easily 
grep for it?

Jules