Suspicious sshd log messages in my syslog

[Logu]

Hello All,

I'm using OpenSSH 4.3p2. I'm getting few messages in my syslog and it is 
shown below,

Aug 02 11:15:19 foo sshd[4381]: Received window adjust for non-open  channel 
0.

I found that sshd received a SSH_MSG_CHANNEL_WINDOW_ADJUST and it executes 
the function channel_input_window_adjust() in channels.c. I like to know how 
this can happen for a non-open channel. Is anything suspicious going in my 
network?

Could anyone share the ideas?

Thanks,
-logu