How do I get IE to drop the domain name from authentication responses

All,

I have a number of internal www servers that run various non MS operating systems which are not tied to the windows domain in any way. They are secure www sites and require authentication.

When I connect to one via IE on a domain joined workstation or server (ie 8 & 9) I am unable to authenticate because I can not remove the domain name from the authentication credentials that IE is passing back to the www server.  I get an authentication prompt for user name & password with the domain pre populated.

How the heck to I get IE to NOT pass the domain name as part of the authentication process. I've tried putting .\ in front of the user name but to no avail.

Thanks,

Steve D.