ZFS to support chflags?

I just moved /usr over to a zpool on my -CURRENT system. Performance and 
stability are both excellent so far. (Thanks Pawel!) However I noticed that 
setting FS flags on files with chflags is not supported. Would it be 
feasible to add support for flags on ZFS, and if so are there plans to do 
so?

If not (and/or in the meantime), are there any places in the base system 
where flags are required for normal operation? (/var maybe?)

Thanks,

JN