I report here a tested and working patch to manage proxy arp on shaper device.
Details are on readme.txt file attached.
I had problems using only a patch file, if someone could tell me what is the 
right command to make a diff file for all kernel source tree.... (I tried 
with "diff -ur tree.orig tree.modified > diff_file" but also other useless 
data are reported... :-()
Thank you
Best Regards
Roberto Arcomano