I have a broadband ADSL line with plus.net in the UK. Having checked the modem there is no firewall or any weird features enabled.

But since I arrived at the apartment (the broadband already being installed), I cannot log into Twitter nor update any of my wordpress blogs (I can browse them and log in, but cannot save any edits or new posts). It only seems to affect these two sites in their unique ways.

If I take the netbook I use in this place out to say a McDonalds or some other wifi access point then these sites work fine again.

Anyone know what could possibly be preventing access of the pages in question? The only thing common to these pages are the POST response they are expecting. But POST form submission works fine on other sites...