Error "Cookies are not enabled" in Internet Explorer if underscore in the hostname

"Cookies are not enabled."

"A potential security vulnerability exists in Internet Explorer versions 5.5 and 6.0 in which a malicious user could create a URL that allows a Web site to gain unauthorized access to cookies that are stored on a client computer and then (potentially) modify the values that are contained in these cookies. Because some Web sites use cookies that are stored on client computers to store sensitive information, this security vulnerability could expose personal information. Security patch MS01-055 corrects this security vulnerability by preventing servers with improper name syntax from setting cookies names."

"A "name" (Net, Host, Gateway, or Domain name) is a text string up to 24 characters drawn from the alphabet (A-Z), digits (0-9), minus sign (-), and period (.). Note that periods are only allowed when they serve to delimit components of "domain style names". (See RFC-921, "Domain Name System Implementation Schedule", for background). No blank or space characters are permitted as part of a name. No distinction is made between upper and lower case.

You can use any one of the following workarounds:

• Change the fully qualified host name of the server so that it is compliant with the naming conventions defined in RFC 952.
• Create a URL/Redirection document so that users are redirected to servername.domain.com instead of server_name.domain.com.
• Change session authentication on the Server document's Internet Protocols tab/Domino Web Engine tab to Disabled. Because the Sametime Web Administration Tool requires Web SSO to be set to enabled (Single-Server or Multi-Server), you will need to implement a workaround as documented in "Sametime: Unable to Administer the Server when Web SSO is Disabled" (#1090310 ).