[newbie] pthread.h doesn't work.

Hi! I've quite recently installed LM8.0 Before I used LM7.2 I have some code that uses pthreads.h, and with Mandrake 7.2 everything worked fine. But after I installed 8.0, it just won't compile. It says something like, pthread_create undefined, or undeclared use of pthread_create. I get

[newbie] pthread.h

I'm trying to install a package called Magellan - it needs pthread.h - Does Linux Mandrake 7 come with this? Thanks. Glen BTW, Thanks for your help Steve for the previous question :)