Really weird problem with login/passwd when using ttyS0

Hi,

i've a really weird problem with login and passwd when using ttyS0: when i hit the return key (enter) it doesn't do absolutly anything.

---
~ # passwd
Changing password for root
New password:
passwd: password for root is unchanged
---

I need to kill the process using CTRL+C

If i connect using SSH, all works fine.

I'm using buildroot from git and busybox 1.18.3.

Busybox config file here
http://pastebin.com/nLyFPwbx

Buildroot config file here
http://pastebin.com/d2e0Krf4

I tried to redo anything from scratch, but the problem remains :\

Someone can give an hint?

Best Regards,
Daniele Salvatore Albano
____________________________________________________________

                                         |
Daniele Salvatore Albano                | web site:
  IT Consultant                          | http://www.daccii.it
  Website Design and Development         |
  Software Engineer and Developer        | e-mail:
  Linux Servers SetUp And Administration | info at daccii.it
  Embedded Network Solutions             | d.albano at gmail.com

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