extglob not matching explicit leading dot

[Mikel Ward]

Configuration Information [Automatically generated, do not change]:
Machine: x86_64
OS: linux-gnu
Compiler: gcc
Compilation CFLAGS:  -DPROGRAM='bash' -DCONF_HOSTTYPE='x86_64'
-DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='x86_64-unknown-linux-gnu'
-DCONF_VENDOR='unknown' -DLOCALEDIR='/usr/local/share/locale'
-DPACKAGE='bash' -DSHELL -DHAVE_CONFIG_H   -I.  -I. -I./include
-I./lib   -g -O2
uname output: Linux mikel-dev 3.3.2-6.fc16.x86_64 #1 SMP Sat Apr 21
12:43:20 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux
Machine Type: x86_64-unknown-linux-gnu

Bash Version: 4.2
Patch Level: 28
Release Status: release

Description:
A leading dot in extglob pattern fails to expand as expected.

Repeat-By:
    cd $(mktemp -d)
    touch .Xdefaults
    shopt -s extglob
    echo @(.Xdefaults)

should print .Xdefaults
but it prints @(.Xdefaults)

works in ksh93 Version JM 93u+ 2011-06-22