From the FAQ on http://www.namesys.com/ I get 4 Gbytes with 3.5 and 17.6 Tbytes(should be 1 Ebytes, but limited by page cache on 32 bit) with 3.6.

I hear that 4 will raise the limits further, but I guess that'll run into page cache limits.......

From what I remember, ext2 and 3 have limits in the Tbytes range.

HTH, but for a definitive answer, I'd post to the Reiser list.