payment page not showing in IE and safari

hi there i have membership installed and it so far so good however i noticed that in IE and safari (the ones I've tested so far) the register page shows up and then when i click on the sign up blue button the intermediate page where the subscription types show, up to pay via gateway and enter coupon code does not show up.

the page in question shows up in Firefox but not in the 2 browsers as listed above. is there a known bug or is there a reason for this?

please let me know so i can resolve this issue.

here is the site page:
http://yogaandmeditationcourse.com/register

the page after the one above does not show in IE and safari.

thank you

marco