Hi everyone !
I can admit that is it true ...
I'am running zsh 4.0.4 (i686-pc-linux-gnu) on my linux box (Debian GNU/Linux "Woody"). 

<1> <ttypts/7> [Sun May 19 20:20:48] cscm@TuX:~
0>zsh
<1> <ttypts/7> [Sun May 19 20:20:51] cscm@TuX:~
0>unset PATH
<2> <ttypts/7> [Sun May 19 20:20:57] cscm@TuX:~
0>ls
zsh: segmentation fault  zsh
<2> <ttypts/7> [Sun May 19 20:20:59] cscm@TuX:~
139>

GDB say that zsh received signal SIGSEGV, Segmentation fault in hashcmd.
and backtrace give me some thing like that :
(gdb) bt
#0  0x0805d822 in hashcmd ()
#1  0x0806013f in execsubst ()
#2  0x0805e8f1 in execlist ()
#3  0x0805e0c1 in execlist ()
#4  0x0805dbe1 in execlist ()
#5  0x0805d9ad in execode ()
#6  0x0806e085 in loop ()
#7  0x0807044c in zsh_main ()
#8  0x080514d4 in main ()

Thx.

-- 
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