[libvirt] pthread_sigmask undefined reference error

Hi, The latest cvs version has an error when compiling: make[3]: Entering directory `/home/jun/projects/libvirt-0821/src' /bin/bash ../libtool --tag=CC --mode=link gcc -g -O2 -Wall -Wformat -Wformat-security -Wmissing-prototypes -Wnested-externs -Wpointer-arith -Wextra -Wshadow -Wcast-align -Wwrite-strings -Waggregate-return -Wstrict-prototypes -Winline -Wredundant-decls -Wno-sign-compare -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fasynchronous-unwind-tables -o virsh virsh-console.o virsh-util-lib.o virsh-virsh.o -Wall -Wformat -Wformat-security -Wmissing-prototypes -Wnested-externs -Wpointer-arith -Wextra -Wshadow -Wcast-align -Wwrite-strings -Waggregate-return -Wstrict-prototypes -Winline -Wredundant-decls -Wno-sign-compare -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fasynchronous-unwind-tables libvirt.la ../gnulib/lib/libgnu.la gcc -g -O2 -Wall -Wformat -Wformat-security -Wmissing-prototypes -Wnested-externs -Wpointer-arith -Wextra -Wshadow -Wcast-align -Wwrite-strings -Waggregate-return -Wstrict-prototypes -Winline -Wredundant-decls -Wno-sign-compare -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fasynchronous-unwind-tables -o .libs/virsh virsh-console.o virsh-util-lib.o virsh-virsh.o -Wall -Wformat -Wformat-security -Wmissing-prototypes -Wnested-externs -Wpointer-arith -Wextra -Wshadow -Wcast-align -Wwrite-strings -Waggregate-return -Wstrict-prototypes -Winline -Wredundant-decls -Wno-sign-compare -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fasynchronous-unwind-tables ./.libs/libvirt.so ../gnulib/lib/.libs/libgnu.a ./.libs/libvirt.so: undefined reference to `pthread_sigmask' collect2: ld returned 1 exit status make[3]: *** [virsh] Error 1 make[3]: Leaving directory `/home/jun/projects/libvirt-0821/src' make[2]: *** [all] Error 2 make[2]: Leaving directory `/home/jun/projects/libvirt-0821/src' make[1]: *** [all-recursive] Error 1 make[1]: Leaving directory `/home/jun/projects/libvirt-0821' make: *** [all] Error 2 It seems I lack a particular library?? Thanks, Jun