Python + vim + spaces vs tab

[Jean-Michel Pichavant]

Hello,

Does anyone knows a way to configure vim so it automatically select to 
correct expandtab value depending on the current buffer 'way of doing' ?
I need to edit different files, some are using spaces, others tabs. 
Those belong to different projects, and changing all spaces to tabs is 
not an option for me.

I can't make vim automatically comply with the current buffer coding 
style, anyone knows if it is possible ?

JM