[BUG][bash][auto completion] if COMPREPLY contents ":" auto completion doesn't work properly

[Vasily Tarasov]

Hello all,

I suppose I've found a bug;
My bash version:
GNU bash, version 3.00.15(1)-release (i686-redhat-linux-gnu)
Copyright (C) 2004 Free Software Foundation, Inc.
But I also have downloaded bash 3.1 and this bug is reproducible there to.

Actions to reproduce:
1) Create the file test.sh, that contents:

_myfunc()
{
        local cur=${COMP_WORDS[COMP_CWORD]}
        COMPREPLY=( $( compgen -W "qwe:on qwe:off" -- $cur) )
}

complete -F _myfunc myfunc

2) Apply this file to the following bash environment:
. ./test.sh

3) Let's try it:
vass@dhcp0-138 $ myfunc
Press tab once:
vass@dhcp0-138 $ myfunc qwe:o
Press tab secondary:
vass@dhcp0-138 $ myfunc qwe:qwe:o


Note, that if ':" is replaced by something else, for exampe '!'
everything works:
vass@dhcp0-138 $ myfunc qwe!o
qwe!off  qwe!on
vass@dhcp0-138 $ myfunc qwe!off

Please, tell me is it a BUG? If it is  - will it be fixed, where I can
follow the progress (I've found no bugzilla for bash)?
If it isn't a bug, please, advice me a workaround.

Thanks for your work,
Vasily Tarasov.