OpenBTS error

Hi list! When I run ggsn, terminal shows: *fg: 1* *debug: 1* *qos: 0x0b921f* *apn: internet* *net: 192.168.0.0/24* *dynip: 192.168.254.0/24* *pidfile: /var/run/ggsn.pid* *statedir: /var/lib/ggsn/* *timelimit: 0* *gtpclient: Initialising GTP tunnel* *openggsn[7002]: GTP: gtp_newgsn() started* *openggsn[7002]: gtp.c: 719: State information file (/var/lib/ggsn/gsn_restart) not found. Creating new file.* *openggsn[7002]: gtp.c: 740: fopen(path=/var/lib/ggsn/gsn_restart, mode=w) failed: Error = No such file or directory* *openggsn[7002]: gtp.c: 808: bind(fd0=4, addr=bf86f8dc, len=16) failed: Error = Address already in use* *openggsn[7002]: ggsn.c: 498: Failed to create gtp* * * If I run it again addr parameter change but log also indicates that address is already in use. Someone can help me? Thanks! Arturo Rivas.