undefined reference to pthread_create in c program on eclipse (Fedora)

I have a problem in building a c thread program. Program is giving error like "undefined reference to pthread_creat". I searched and found to use gcc options like "gcc -lpthread -o ...."

But I not able to set it for eclipse. I tried to make change in makefile but every time it got replaced with default options. Please help me to set these gcc options and write about where and how to set gcc options in eclipse on fedora 10.

Thanks,

Lokesh