Despite what many claim, I don't believe that the IT industry in general is "Institutionally Sexist", it may well be male dominated, but that isn't the same thing.
It's been my experience from working in both small and (very) large firms from the mid-80s onwards that women in IT are treated equally to their male conterparts. Those that are good do well and those that aren't don't. There may be some discriminiation or sexist attitude, but this seems to be a minority.
While there are female "geeks", most women just aren't interested in technology - to most, it's just a tool to get the job done. And this is reflected in the world of IT.
So it isn't surprising that women make up a minority in IT. Would the Industry benefit from more women in the field? Quite probably, but where are they to be sourced? You can't employ somone who doesn't apply for a position and to employ someone *just* because they are female and not the best qualified/able will not improve male attutudes to women in IT.