sharedlocalstate default - does anybody use this?

[Mariano, Adrian V.]

It has been brought to my attention that in my package (GNU units) I have a 
file that gets changed every day located in datarootdir---but this location is 
for read only files.

The correct place for my architecture independent dynamic file would appear to 
be  sharedstatedir.   However, this resolves to the rather bizarre path 
/usr/local/com.  I can't find any reference to anybody actually using this 
path.   Do all the distributions over-ride this into something "normal"?  The 
fedora units guy tells me it will be /var/lib, for example---and I think with 
redhat the whole /usr directory is supposed to be read only.

So what's the correct practice for my package?  Should I use sharedstatedir and 
not worry about it resolving to a strange default path because mostly it will 
get changed by site defaults?  Or is there some other way to handle this?