Going back 5 weeks, compat-wireless isn't building against 2.6.27.49:
CC [M] /home/philipp/kernel2/build_i586/compat-wireless-2010-08-27/compat/compat-2.6.35.o
/home/philipp/kernel2/build_i586/compat-wireless-2010-08-27/compat/compat-2.6.29.c: In function 'init_dummy_netdev':
/home/philipp/kernel2/build_i586/compat-wireless-2010-08-27/compat/compat-2.6.29.c:156: error: 'struct net_device' has no member named 'napi_list'
make[4]: *** [/home/philipp/kernel2/build_i586/compat-wireless-2010-08-27/compat/compat-2.6.29.o] Error 1
make[4]: *** Waiting for unfinished jobs....
A quick search looks like it was Hauke's patch on 8/17 entitled:
[PATCH 1/3] compat: backport init_dummy_netdev
Thanks,
-Philip