Forward checkout from sub domain

Hi, is it possible to forward / redirect the checkout from a sub domain to main domain, the reason is because the SSL doesn't cover the sub domain.

Alternatively I don't mind removing the checkout and account links from the sub if this is possible as i can put a link on the menu back to main domain.

Thanks for your help

Edited: using OC 1.5.51

Any help please,

I want to try and force the sub domain to use the SSL checkout on main domain, I have tried a redirect in htaccess to redirect the login, register and checkout but this didn't seem to work.

Why can't you move the store from sub domain to main domain?