DNS server not refreshing

[Stephen Williams]

I have been having a problem where other DNS providers around the nation are
not refreshing the DB files on their servers to new information. Apparently
it is remaining in their cache for weeks after the changes are made. As an
example,  a user sending an email has their DNS server direct that email to
the mail server of the old information that was changed weeks ago.  Does
anyone know why this is occurring on some servers and if there is a command
to force a server to refresh/update or update the cache on that server,
possibly from nslookup????


THANKS!!!!!!!