Problems with login

Some members have reported problems with not being able to click into the 'User Name' box and some other places on the site.
I have been unable to duplicate this problem but it seems to happen only with Internet Explorer (IE) version 6.
It would be very useful to know if others have had this problem but not reported it. If you have experienced this, please contact me, or reply here and include information about your browser if you can.
If your are using IE6, you are encouraged to update it as soon as possible. I recommend Firefox as the best replacement because it does not affect your Windows installation at all, and is a smaller download than IE7.