Can't find XK_Num_Lock when trying to compile gtk+3.0.10

[twurgl goodyear com]

I am on SuSE 10.1 and believe I have all
the prerequisite packages installed, yet I get:

  CC     gdkkeys-x11.lo
gdkkeys-x11.c: In function 'get_xkb':
gdkkeys-x11.c:235: error: 'XK_Num_Lock'
undeclared (first use in this function)
gdkkeys-x11.c:235: error: (Each undeclared
identifier is reported only once
gdkkeys-x11.c:235: error: for each function
it appears in.)
make[4]: *** [gdkkeys-x11.lo] Error
1
make[4]: Leaving directory `/u/rds4020/t901353/src/gtk+-3.0.10/gdk/x11'
make[3]: *** [all-recursive] Error 1
make[3]: Leaving directory `/u/rds4020/t901353/src/gtk+-3.0.10/gdk'
make[2]: *** [all] Error 2
make[2]: Leaving directory `/u/rds4020/t901353/src/gtk+-3.0.10/gdk'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/u/rds4020/t901353/src/gtk+-3.0.10'
make: *** [all] Error 2

Any help appreciated.
thanks
tom