snmpwalk core dump

when i do a snmpwalk i always get a core dump
WHY ?

squid-2.3.STABLE1-1
ucd-snmp-4.0.1-5
RH 6.1
mrtg with squid works fine

[root@lilo /root]# snmpwalk -p 3401 -m /etc/squid/mib.txt localhost public enterprises.nlanr
enterprises.nlanr.squid.cacheSystem.cacheSysVMsize.0 = 7244
enterprises.nlanr.squid.cacheSystem.cacheSysStorage.0 = 5532814
enterprises.nlanr.squid.cacheSystem.cacheUptime.0 = Timeticks: (1210536) 3:21:45.36
enterprises.nlanr.squid.cacheConfig.cacheAdmin.0 = admin@pcn.de
enterprises.nlanr.squid.cacheConfig.cacheSoftware.0 = squid
enterprises.nlanr.squid.cacheConfig.cacheVersionId.0 = "2.3.STABLE1"
enterprises.nlanr.squid.cacheConfig.4.0 = "ALL,1"
Segmentation fault (core dumped)
[root@lilo /root]#