[AGENT++] what happened with my mib files?

[Jinnee]

hello friends:
when i compile my mib files, it has some error i have never seen before. see as follows. Please help me what happened?
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arm-linux-g++ -g -Wall -c -o bluetop_bmc10_mib.o -I../include -I../../../include -I../../../../snmp++/include bluetop_bmc10_mib.cpp
arm-linux-g++ -g -Wall -o agent agent.o snmpv2_conf.o snmpv2_smi.o snmpv2_tc.o bluetop_bmc10_mib.o  -L../../../lib -L../../../../snmp++/lib -lpthread -lagent++ -lsnmp++ -L../../../../libdes -ldes
bluetop_bmc10_mib.o(.gnu.linkonce.t._ZN7Agentpp10DefaultLog3logEv+0x88):../../../include/agent_pp/List.h:168: undefined reference to `Agentpp::AgentLogImpl::AgentLogImpl[in-charge](_IO_FILE*)'
bluetop_bmc10_mib.o(.gnu.linkonce.t._ZN7Agentpp10DefaultLog3logEv+0x120):../../../include/agent_pp/List.h:1140: undefined reference to `Agentpp::DefaultLog::instance'
bluetop_bmc10_mib.o(.gnu.linkonce.t._ZN7Agentpp10DefaultLog16create_log_entryEh+0x8c):../../../include/agent_pp/List.h:999: undefined reference to `Agentpp::DefaultLog::entry'
bluetop_bmc10_mib.o(.gnu.linkonce.t._ZN7Agentpp10DefaultLog9log_entryEv+0x34):../../../include/agent_pp/List.h:1075: undefined reference to `Agentpp::DefaultLog::entry'
bluetop_bmc10_mib.o(.gnu.linkonce.t._ZN7Agentpp10DefaultLog16delete_log_entryEv+0x64):../../../include/agent_pp/List.h:970: undefined reference to `Agentpp::DefaultLog::entry'
bluetop_bmc10_mib.o(.gnu.linkonce.t._ZN7Agentpp10DefaultLog4initEPNS_8AgentLogE+0x6c):../../../include/agent_pp/List.h:952: undefined reference to `Agentpp::DefaultLog::instance'
collect2: ld returned 1 exit status
make: *** [agent] Error 1
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