Slow sftp/scp access despite fast network

Hello, trying to track down this problem. Between two computers 
(gutowksy,ramsey), I get quite reasonable access via web (wget measures 
578.09 KB/s, with ramsey serving), but when transferring via sftp or scp, 
the access crawls to a halt (starts at 30 kb/s then stalls, jumps to 30 
kb/s then stalls ...). It takes 1 min to transfer a file via wget, but 3/4 
of an hour via sftp!? Iperf also measures a reasonable connection rate 
between the two)

the problem persists from various boxes running a range of openssh 
versions connecting to gutowksy (can't transfer in reverse using ramsey's 
sftp-server which works, because it's behind a firewall I don't control 
...). So, it seems that the OpenSSH_3.5p1 pat OpenSSH_3.* running on 
gutowsky is failing somehow (installed as corresponding redhat package).
Anyway, I then compiled a new version (openssh-4.2p1.tar.gz) and ran it on 
a different port (just so I don't lock myself out - gutowsky's several 
hundred miles away!) - but found no change at all. Any ideas?

p.s. I saw the message-list-archive post about slowness on solaris,
and tried altering misc.c to become:
/* disable nagle on socket */
void
set_nodelay(int fd)
{
        int opt;
        socklen_t optlen;

        return;

...

}

-> i.e., I just through in the return as suggested (to jump out of 
subroutine?)

kjharris@sdf.lonestar.org
SDF Public Access UNIX System - http://sdf.lonestar.org