completion considers equals sign (=) its own word?

[bebarino]

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 -Wall
uname output: Linux swboyd-laptop 2.6.31-16-generic #53-Ubuntu SMP Tue Dec 8 
04:01:29 UTC 2009 i686 GNU/Linux
Machine Type: i486-pc-linux-gnu

Bash Version: 4.0
Patch Level: 33
Release Status: release

Description:
        When completing options for git I used to be able to get a list
        of pretty formats by completing the --pretty= option. The option
        ends in an equals sign, so the completion looks for the word
        --pretty= in the COMP_WORDS array. It turns out that --pretty and =
        are considered two separate words in bash4, but considered one word
        in bash3. Is this intended?

        I know I'm reporting this on patch level 33, but I've seen it on
        patch level 35 too.

Repeat-By:
        1) Install git's completion script (in contrib/completion of
                http://kernel.org/pub/software/scm/git/git-1.6.5.6.tar.gz)
        2) Try to complete
                git show --pretty=<TAB><TAB>
        
        and you get a list of filenames instead of a list of pretty formats.