Fortunately, there’s a way to tell Google and MSN not to use the ODP
description for your web site. You can direct Google and MSN not to use the ODP
as a source by adding a new Meta tag to your
web pages.

To prevent all search engines (that support the Meta
tag) from using the ODP description for the page’s description, use the
following HTML tag:

<META NAME=”ROBOTS”
CONTENT=”NOODP”>

To specifically prevent Google from using this information for a page’s
description, use <META
NAME=”GOOGLEBOT” CONTENT=”NOODP”>. If you just want
to prevent MSN from using the description, use <META
NAME=”msnbot” CONTENT=”NOODP”>.

Note that once you add this Meta tag to
your pages, it may take some time until a new description of your web page will
appear in the search results of Google and MSN.

You might wonder why Yahoo does not support the NOODP tag. Yahoo operates
its own directory so it does not need to pull the web page descriptions from
the ODP.

Source: www.axandra.com