SSL VPN web-only mode and root-relative paths

We have configured an access to a web application via web-only mode (http / https) at an Fortigate 600c, but we have problems with the root-relative paths. Example, We start with a url something like http://vpn.mydomain.net/p...e/app/folder/login.php When we login at application and do a call ajax to a function in url='/app/folder2/utils/functions.js', the Fortigate 600c shows a 403 forbidden. It's because it not changes/catches the URL in the correct form and dont add '/proxy/http/myhostname/' substring. The result and wrong http request is http://vpn.mydomain.net/a...er2/utils/functions.js And the correct way would be http://vpn.mydomain.net/p...er2/utils/functions.js If you edit with browser web console and resend the request, you obtain 200 status. With relative path as ../folder2/utils/functions.js or absolute path [link]http://myhostname/app/folder2/utils/functions.js[/link] the  web-only mode works well. Is there is any form to catch this kind of requests? Tunneled proxy than replacement proxy per example? Via command CLI console?