Aliases fail in command substitution in noninteractive mode.

[fsateler]

Configuration Information [Automatically generated, do not change]:
Machine: i486
OS: linux-gnu
Compiler: gcc
Compilation CFLAGS:  -DPROGRAM='bash' -DCONF_HOSTTYPE='i486' 
-DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='i486-pc-linux-gnu' 
-DCONF_VENDOR='pc' -DLOCALEDIR='/usr/share/locale' -DPACKAGE='bash' -DSHELL 
-DHAVE_CONFIG_H   -I.  -I../bash -I../bash/include -I../bash/lib   -g -O2
uname output: Linux genoa1 2.6.16-1-k7 #2 Thu May 4 18:35:10 UTC 2006 i686 
GNU/Linux
Machine Type: i486-pc-linux-gnu

Bash Version: 3.1
Patch Level: 14
Release Status: release

Description:
        Aliases don't work correctly in command substitution when in 
        noninteractive mode. They do work when in interactive mode.
Repeat-By:
        The following script illustrates the problem:

        #!/bin/bash
        alias foo=echo
        echo `foo hi`
        echo $(foo hi)

        When I call it, I get a "foo: command not found" error. However, if I
        insert those commands manually in my shell, they work as expected.