2.9p2 behaves different from 2.5.2p2 on tunneling issue

[Markus Friedl]

On Tue, Sep 18, 2001 at 10:38:41AM +0200, Corinna Vinschen wrote:
> On Sat, Sep 15, 2001 at 11:06:51AM +0200, Markus Friedl wrote:
> > On Sat, Sep 15, 2001 at 01:57:02AM +0200, Corinna Vinschen wrote:
> > > On Fri, Sep 14, 2001 at 07:54:05PM +0200, Markus Friedl wrote:
> > > > because 2.5 had a 'broken' implementation like the older ssh
> > > > servers. it was 'fixed' in 2.9, now you see this behaviour
> > > > against older, broken servers. the problem is that
> > > > the drafts for the protocol have changed since 1997.
> > > 
> > > Shouldn't 2.9 behave `broken' when it knows that it communicates
> > > with an old `broken' server?
> > > 
> > > > > in contrast to 2.5.2p2 as client using the same server?  And
> > > > > how can I workaround that using 2.9p2?  I'm not that keen to
> > > > > stick with 2.5.2p2 on that machine...
> > > 
> > > Otherwise there's neither a workaround nor a sort of a compatibility
> > > mode in 2.9.  Which means I'm stuck with 2.5.2 unless the server
> > > side decides to upgrade :-(
> > 
> > look at compat.c, we have many emulations of 'broken' code.
> > i'll look into this, but i think it's too ugly.
> 
> Could you give me some hints what I have to look at?  I'm a bit lost
> since I haven't found a documentation of the supported bugs in compat.c.
> What is the change between 2.5.2 and 2.9 which results in 2.9 not
> keeping the connection when communicating with old servers?

in 2.5 the client requested a 'session' for -N, 
but did not execute anything.

however the 'session' this is not necessary at all.