aix broken?

[<tomh@VNET.IBM.COM> (?)]

Greetings. I find myself working on an aix box (rs6000, 4.1.3) these days.

When I run zsh 2.5.3, it will unexpectedly segmentation fault at
seemingly innocuous points. For example, whenever I attempt to cd to
/tom, a local directory on my machine, it segmentation faults.

zsh 2.6.12 doesn't segmentation fault, but its tty interface is
broken. In particular, it forgets what <backspace> means, and it
doesn't repaint the line correctly after a, for example, ^a^k.

I'm used to running 2.5.3 on solaris 2.3, where zsh works
beautifully. My settings are

    setopt APPEND_HISTORY       # don't overwrite the history file
    setopt HIST_NO_STORE        # don't store "fc" commands
    setopt HIST_IGNORE_DUPS
setopt AUTO_CD          # don't require "cd"
setopt AUTO_NAME_DIRS   # terse directory names
setopt CORRECT          # correct spelling of commands
setopt EXTENDED_GLOB    # treat #, ~, and ^ special
setopt GLOB_DOTS                # turn off requireing "."'s
setopt INTERACTIVE_COMMENTS     # allow comments
setopt LIST_TYPES               # trailing @ or / or *
setopt NO_CLOBBER
setopt RCQUOTES         # allow 'who''s' as well as 'who'\''s'
setopt SH_WORD_SPLIT    # parameter values are  split  into  separate  words

Thanks very much for any help you may provide.