Joomla 1.0.12, sh404SEF and Forme 1.0.3.

When SEF is enabled forme doesn't function properly don't know if it is SEF problem or forme, created a form and a menu link-URL to the form, first visit to the site and forme everything seems to function OK however after submitting the form the page remain on thank you page and every subsequent visits to site the thank you page is displayed an not the form.

Site is
http://vmsh.protechsystems.us/forme/