Problem: Temporarily unavailable due to scheduled maintenance

Hello,

I have a major problem.

I was trying to automatically update WordPress to version 3.2.1.

It took a long time this time. Normally it is a proces of twenty seconds, but this time things weren’t going as smooth as it should be.

Now my site gives an error and I can’t access the control panel anymore.

The whole site is down!

This is the error message: Temporarily unavailable due to scheduled maintenance. Please try again in a few minutes.

In Dutch:
Tijdelijk niet beschikbaar vanwege gepland onderhoud. Probeer het over enkele minuten nog een keer.

What can I do to restore the site again?

Thanks in advance.

Edit: after a few minutes, I still cannot access the site or the dashboard, but I get the following message:

—
Fatal error:

Allowed memory size of 262144 bytes exhausted (tried to allocate 122880 bytes) in /home/*****/domains/**********.nl/public_html/wp-admin/includes/dashboard.php on line 88
—

***** = removed letters

Please help?