'dd' local works, but not over net, help as to why?

["LA Walsh" <law@sgi.com>]

I'm sure there's an obvious answer to this, but it is eluding me.

If I am on my local laptop, I can 'dd' an 8G partition to a
removable HD of the same or slightly larger size (slightly large
because of geometry differences).

If I am on my desktop, "I can 'dd' the same size partition to
a slightly larger one -- again, no problem.

But if I use:

dd if=/dev/hda2 bs=1M|rsh other-system of=/dev/sda2 bs=1M, I
get failures of running out of room on target.  I've tried
a variety of block size ranging from 1K->64G, but no luck.

Is there something in the networking code that's preventing me
from transferring more than a 2 or 4 G limit?

I just wanted an exact image off onto another system.  Would
seem to have been straight forwared. but I guess not?  

Thanks in advance for any work-arounds and explanations...

-linda