compilation error

Hello i have some problems with the compiliation of bopm

I always get the error msg

online@shell3:~/ircd/bopm-3.1.2$ make
Making all in src
make[1]: Entering directory `/home/online/ircd/bopm-3.1.2/src'
make  all-recursive
make[2]: Entering directory `/home/online/ircd/bopm-3.1.2/src'
Making all in libopm
make[3]: Entering directory `/home/online/ircd/bopm-3.1.2/src/libopm'
/bin/sh: fork: Resource temporarily unavailable
Making  in src
/bin/sh: fork: Resource temporarily unavailable
make[3]: *** [all-recursive] Error 1
make[3]: Leaving directory `/home/online/ircd/bopm-3.1.2/src/libopm'
make[2]: *** [all-recursive] Error 1
make[2]: Leaving directory `/home/online/ircd/bopm-3.1.2/src'
make[1]: *** [all] Error 2
make[1]: Leaving directory `/home/online/ircd/bopm-3.1.2/src'
make: *** [all-recursive] Error 1

I don't know why that happens

Regards Daniel :)