An example of the problem can be found at http://www.comcept.net/crash.htm. I have called Microsoft but the support department is not very helpful with new bugs. They were even unable to report the bug to the IE team. All they could help with was hotfixes already released by Microsoft.
Thanks to AH who posted this comment on the IE blog:
IE 6.0 crashes on all platforms with August 2006 Security Update installed Visit http://www.comcept.net/crash.htm and follow the instructions. This will demonstrate Internet Explorer 6.0 crashing on any platform (Windows 2000/XP/2003 with any Service Pack) if you have installed the August 2006 Security Update (918899) even if you cleared the checkbox next to HTTP 1.1 protocol or installed the hotfix 923762. The exact error message varies, but is something like this: Title: "IEXPLORE.EXE - Application Error". Text: The instruction at "0x4a5b19d6" referenced memory at "0x00000020". The memory could not be "read". This particular issue is related to the use of the "popup" window API after installing the August 2006 Security Update. This is the cause for frequent IE crashes when using web-based applications such as Comcept and ProSight Portfolios.