No TTY after su -- can't edit history!

[Jerzy Sobczyk <J.Sobczyk@xxxxxxxxxxxx>]

Hi!
I have just got zsh-2.6-beta10 succesfully compiled it under Solaris 2.3
and after playing a while I have noticed following feature:
when I do following steps:
	1. su
	2. su - user
	3. zsh
then I can not edit the history.
As far as I could trace the problem it comes from the fact that
in step 2 Solaris does not change the owner of /dev/pts/? and as a result
in zsh the symbol TTY is empty and can not be set.
I am not sure if this should be fixed in zsh or in Solaris.
	Jerzy
PS.
I am not subscribed to the list so please mail me directly.
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Jerzy Sobczyk              ____________ ___     Institute of Control and
J.Sobczyk@xxxxxxxxxxxx    /  /     |  |/  _\    Computation Engineering, 
                         /  /  /|  |  |  (____         Warsaw University 
tel.+48 2 660 7297      /  /  _>|  |  |\____  \            of Technology
fax.+48 22 253719      /__/__/__|__|__|_____)  \       Nowowiejska 15/19
tlx. 813 307 pw pl    /________________________/   00-665 Warsaw, POLAND 
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