pthread problem

Hi all!
I am working on unix systems.I am programming in c.
I have got some problems with pthread.when I use pthread_create to creat a thread it says:
(.text+0x3a): undefined reference to `pthread_create'.

same is the problm with pthread_kill.
Can anyone help me out here.
Thanks.
vij.

I think you are not linking the correct thread library. Can you post here some code and the way you invoke the compiler..!

Compile with -D_REENTRANT to tell standard headers you are using threads
Link with -lpthread to link with the pthreads library