SMC2804 file upload problem

Hi folks,

I have just gotten myself a SMC2804WBR v2 Barricade wireless router.
Everything works fine except for one thing.

I can't upload files.

i.e.
1. I can't scp files to a remote server
2. I can't upload files via a webpage. If I wanna put a attachment via
Yahoo mail, I couldn't. The browser just keeps loading.

If I connect straight to my cable modem, uploading works fine.

Oh, I do not have firewall in the router enabled.

help?

best regards
terry