Any risk in increasing BLCKSZ to get larger tuples?

Hi -
    I'm thinking about using postgres for an app that will store
various email messages which might (although probably not likely) be
larger than the builtin limit for tuples.  Is there anything I should be
aware of before changing the below value and recompiling?

Also, it looks like the TOAST stuff would solve this (right/wrong?), but
it's not going to be ready for 7.1 (right/wrong?)

Thanks!

from src/include/config.h
/*
 * Size of a disk block --- currently, this limits the size of a tuple.
 * You can set it bigger if you need bigger tuples.
 */
/* currently must be <= 32k bjm */
#define BLCKSZ  8192