Bug in filename expansion

[Ray Van_Tassle <rayvt@xxxxxxxxxxxxxxx>]

I do this:
>touch zzayy                                                             ~/temp
>touch zzbyy                                                             ~/temp
>touch zzxyy                                                             ~/temp
>ls zz*                                                                  ~/temp
zzayy  zzbyy  zzxyy

>ls zz(a|b)yy                                                            ~/temp
zzayy  zzbyy

>ls zz^(a|b)yy                                                           ~/temp
zsh: no match
 
Seems wrong.  According to the man pages, the 2nd command should give me
the files that start with "zz", then have either "a" or "b", and end with "yy".
OK.
But the 3rd command should give me the files that start with "zz", then have
a character OTHER than "a" or "b", and end with "yy".
It should give me "zzxyy", but it doesn't.
 
This is with zsh-2.6-beta20
 
Thanks,
Ray Van Tassle
rayvt@xxxxxxxxxxxx