Symptom
When you browse a secure Web site an alert box with this message appears:
"The identity certificate uses an unknown signature algorithm."
Solution
All versions of Internet Explorer later than 4.5.1, including all Mac OS X versions, are not affected by this issue.
Information about products not manufactured by Apple is provided for information purposes only, and does not constitute Apple's recommendation or endorsement. Please contact the vendor for additional information.
The following document can help you search for a particular vendor's address and phone number:
Document 17159: "Locating Vendor Information"