Http proxy problem

I have a problem when using safari by http proxy in our office. We can't acces to internet. I have match http proxy setting with my Ipod touch. Ipod can acces the internet but Ipad can not. I see that in the password template on Ipad after we fill in password and back to previous menu then back again to password template that the space is blank, meanwhile on Ipod touch I can see many dot in password space.