Hi Da,
I have been doing cross compiles for the fedora arm kernel this week. You might try setting the PATH to include the path to the cross compiler if it isn't part of the normal path and then try something like:
export ARCH=arm
export CROSS_COMPILE=armv5tel-redhat-linux-gnueabi-
make
CROSS_COMPILE should be the prefix of the copmiler used for all the cross compile commands.
I have made a quick wiki page at (still need to format it properly):
http://sourceware.org/systemtap/wiki/SystemtapOnFedoraArm