aspx frames do not display correctly on browsers other than IE

My company home page is made of two frames with aspx ending. All computers are PC with microsoft installed. The home page displays correctly on Internet explorer but on other browsers the width of the frame is shorter, some text is cut off (it looks like there is a padding problem).
In the past we had a similar problem with pdf documents. A file named document.aspx couldn't be open on safari until someone got the idea to name all files document.pdf.aspx.
I'm wondering now if changing leftframe.aspx to leftframe.html.aspx will solve the problem.

The IT service of my company is microsoft minded and doesn't look for solutions that can benefit the Mac world. But maybe if I can present a solution they will agree for a change.

Can someone of you, asp.net expert, give me a hint? Can this little change from frame.aspx to frame.html.aspx be tested on your computer? Or do you know another solution?

Many thanks, I appreciate your help.

Paldo

This really isn't a good place to ask that question as few if any of us have access to test that, someone might. But I would suggest also asking here:

http://forums.iis.net/

I would also recommend that you try your idea out yourself. Tell them it worked for the PDF files and that it might for the html files as well.