asterisk users - Mar 2006 - Destroying a SIP extension doesn't destroy voicemail box?is this a bug?

Hi all,

I'm using Asterisk@home 2.5, and i've done:

1-Create a SIP extension.
2-Leave there a Voicemail message
3-Remove SIP extension

Then I've create another SIP extension but with the same number of the
above one.
I found imediately a voicemail message in my voicemail box.

Is this a bug? Am I doing something wrong?

Best regards,
Marco Mouta