lucy24 - 2:27 am on Jan 16, 2013 (gmt 0)
Tangential answer: PLEASE don't use relative links in the ../ form in css. They're undesirable at the best of times; in css you absolutely-- haha --need the site-absolute form with leading / (directory slash). Personally I make an exception when everything is happening within the same directory. Some folks, ahem, naming no names, don't admit the exception.
This is not likely to solve your problem, but try it just to clean away one variable.
Did you pore over the relevant page at caniuse dot com? The line that jumped out at me was
Partial support in IE9 refers to the fonts only working when set to be "installable".
Is your font "installable"? (Is this something you can change? Over on my side of The Great OS Divide, the big variable is "embeddable". And officially you can't change that; it's built into the font.)
I'm also worried by the discovery that rules with ttf and otf don't work at all in MSIE <9. Any earlier and you have to use eot-- which, of course, nobody but MSIE has ever used. Is that what the fallback font is for?