checksumming on a DP83820

[Christian Widmer]

does anybody know the DP83820 which is used on the GigaNix NIC and
can awnser me the folloing question or knows where to ask. 

the DP83820 supports IP/UDP/TCP checksumming. the chip docu say you
can mark the transmit descriptior when it contains a IP, UDP, TCP header.
1) is it possible for udp to spread multiple descriptios and the checksum
   will be calculated? 
2) if so can it be bigger than a jumboframe?

i don't find any awnsers in the chip docu from national. i think 1) could be
possible but 2) not. am i right?

thanks
chris