Slow ajax with webreick

Using ie, webrieck ( all on win xp) and rails-0.13.1
I find that I get very very slow response when using ajax to update a
form.
Much slower than a regular page load. So bad I have considered dropping
ajx
completely
In my production env I use apache/fcgi and it is instantaneous
Any suggestions? ( apart from use fcgi in dev!)
Thanks
Paul