Changing the expiration date after the key has expired

[Vincent Panel]

Hi,

I just wondered if it was possible to postpone the expiration date
after it has been set and/or after the deadline has been reached.

2 years ago, I created a personal key and set the expiration to 2y, so
it has now expired. It looks like I can change the expiration date (of
the primary key) in gnupg software "using edit-key". My subkey expired
too, so I have generated a new one.

I've tried to export the result and put it on the mit keyserver but it
failed. According to the message I've read, it was because my userids
wer signed by two keys (which is more or less wrong : I've checked and
they are signed twice by the same key, but at different dates). What
is strange is I've tried another keyserver and it worked (without
removing the expired signature).

But, well, the real problem is that now, even if my new subkey has
been imported successfully, the primary key on the keyserver still has
the old expiration date set - i.e. the primary key has expired : do
you know if I can update the key on the keyserver so that it is aware
of the new expiration date ?

Thanks,

Vincent