[Hampshire] cvs history query

Hi,

I'm looking for a way to tell when a tag was applied to a file in a CVS
repository?

>From reading some documentation I though I could do this with the "cvs
history" command, but so far I don't seem to have managed it.

As far as I can tell this information should be recorded in
CVSROOT/history but the file format is somewhat obscure and when I try to
use cvs history it doesn't return what I was expecting.

Can someone suggest the correct incantation of the cvs history command to
extract information about who applied what tag when or point me towards
some decent documentation (I've read several sets of documentation on cvs
history which seem rather vague or incomplete) on the command?

Thanks,

Andy