automatic boot fschk in karmic works in background for large partitions

Starting from Karmic fschk checks partitions in backgound when the partitions is very large, so the boot continue but the partition is not mounted and ready to use until the fschk has finished the check.
That is fine because otherwise the boot could stop for several minutes waiting for the check, but in some special conditions can produce some mess, i.e. if the large partition to check is the /home.
Is it possible to determine which partition can do the background check and wich other needs to force the kernel to wait for the end of the check?

Thx a lot.