MM Messages transfer

[manjupatil]

Dear All,

Please find the below scenarios:

1) I m having 6500 as my desk phone with voice mail
feature on MM (6500 VM Ext).
2) Now we are going to change 6xxx to 8xxx dial plan. So my
desk phone will be 8500 & VM extension will also be 8500.
3) But in VM if i replace 6500 to 8500, then my all old
messages will be deleted.

So I don't want to loose my all messages.

So please suggest is there any way to retain my old messages even after replacing 6500 to 8500 in Voice mail.

The above scenario is for a single user, so i have almost 200 users mail boxex on MM. So we need to replace the 6xxx extension & VM extensions to 8500 & also have to retain their old messages.

Thanking you in advance,

Thanks,
Manju