Cita:
Iniciado por mauritosuarez 
Prueba hacer un print_r($_SESSION); para te muestre todas las variables de session que tienes asignadas.
Saludos.
hola amigo en la primera pagina hago lo que me pedistes del print y me arroja esto:
Array ( [checkChamiloURL] => http://localhost/chamilo/ [starttime] => 1414774704 [is_platformAdmin] => [is_allowedCreateCourse] => [is_courseAdmin] => [is_courseMember] => [is_courseTutor] => [is_courseCoach] => [is_allowed_in_course] => [is_sessionAdmin] => [studentview] => teacherview [ascii_math_loaded] => [user_id] => 4 [_user] => Array ( [complete_name] => eduardo villegas [complete_name_with_username] => eduardo villegas (shino) [firstname] => eduardo [lastname] => villegas [firstName] => eduardo [lastName] => villegas [phone] => [picture_uri] => [official_code] => SHINO [status] => 5 [active] => 1 [auth_source] => platform [username] => shino [theme] => [language] => spanish [creator_id] => 0 [registration_date] => 2014-10-25 03:04:19 [mail] =>
[email protected] [email] =>
[email protected] [user_id] => 4 [last_login] => 2014-10-31 17:57:23 [lastLogin] => 1414771043 [avatar] => http://localhost/chamilo/main/img/unknown.jpg [avatar_sys_path] => C:/wamp/www/chamilo/main/img/unknown.jpg [avatar_small] => http://localhost/chamilo/main/img/unknown_22.jpg ) [loginFailed] => [chatHistory] => Array ( ) [openChatBoxes] => Array ( ) [window_list] => Array ( ) )
y en la otra pagina me arroja solo esto:
Array ([user_id] =>)