Well, I'm now on firmware 1.3... rooted. Many surprising things or things to get used to. The browser is now by default in landscape orientation (it was in portrait mode), with a new homescreen... I should have thought to save my favorites
"SonyPrsT1Home" alternate homescreen is already better than the original one, for people beginning several books simultanously. Thank you Gustav and Simon for your replies. I have internet connection behind a proxy where I sit right now, so I can't use it for the eReader
(a problem with many android devices, you have to install something as "transproxy" to connect with a proxy, shame on google for this)
edit : Transproxy can't be installed (probably because of the lack of iptables on this minimal version of android)