好容易有两天假期折腾下面这个问题了

这是我在ubuntu的launchpad上的提问。也应该转到水木上去，恩。

can not upload anything

1. I can't send email attachment via webmail or email client like evolution unless the attachment is very tiny, say below 1k
2. I can't upload file via ftp client like lftp, ftp, scp

I think the problem may be the C library or the kernel.
I investigated this issue. I download a source of ftp. (apt-get source ftp) I added some 'printf's to the source to find this:
it stops responding after a call to write(filedescriptor, buf, size), or a call to close(). I locate these calls in the source of ftp. The first few calls to write() will work.

My network is good. Anything is fine if I use MS windows. I tried to change the libc6 (and libc6-i686) from 2.7-10ubuntu4 to 2.7-10ubuntu3. I also tried to change a version of kernel, say from 2.6.24-21 to 2.6.24-18. The problem is still there.

Hope somebody can help me. Below are some detailed information.

uname -a
Linux kahler-laptop 2.6.24-18-generic #1 SMP Wed May 28 20:27:26 UTC 2008 i686 GNU/Linux

Ubuntu 8.04 GNU C version 2.7-10ubuntu4