permanent version storage???

[chickenlegs]

Can someone please enlighten me as to what the following message means?
"the document is on a volume that does not support permanent version storage"
This message appears when trying to save a (version) of a keynote presentation on my MB. The MB does not have Time Machine running - could this the reason?
As a separate issue, keynote is now taking an age to save documents under Lion. Is this connected to the same issue?

 

[Gamoe]

I found the answer (for me) here:

Were you working with files on a digital camera or USB flash drive?

If so — and if the volume uses something like old MS-DOS — then the information presented by Lion is normal.