PPTP VPN browse problem
 

First, I`m sorry if u can´t understand some words, my english is not to good =) I´m from Argentina.
This is my problem: I can connect to my VPN server, I use a Debian Sarge, with kernel 2.6.5 with the mppe patch. The users with Windows XP can logged in to the VPN, but when i mark the option "Requires encryptation data", i still can connect to the VPN but i can´t browse on some pages. An example, the MSN pages (hotmail.com, passport.net). When i don´t mark the "require encryptation data" option, i can browse in all the pages, including that pages.

If someone can help me, plizzz, thank´s anyway