MSIE is broken

At least it seems that way.
The symptoms are as follows:
We are using uPortal and we want the user to be able to download a file, that's pretty straight-forward, but the problem is that when you tell MSIE to open the download dialog it pops up just fine, asking the user if they want to open the file (which is a text file) or to save it to disk.
The strange part is that the url shown on the dialog is rewritten, the dots have become underscores. I don't know why that is but my theory is that the browser rewrites the filename so that it will not have any program associated with it, thus "protecting" us from malicious content.
But that's just my theory. The result is that of you click "save" the file can not be found. This sucks. I don't know if it's a feature you get when installing SP2 on XP but it's reeeeeeeeeeely bad hacking.

Well, well, on another note i'd like to say that some people at my job are ignorant and stubborn and to some extent realy stupid. I'm sorry but I'm angry!!!!