proc_info[process,gdiobj(or userobj)] returns 0 in some case

Steps to reproduce:

• zabbix_agentd -t proc_info[iexplore.exe,gdiobj] returns ordinary value like below.
  
• but zabbix_get and zabbix GUI always return 0 like below.
   
• AFAIK only processes that do not run as SYSTEM user(like iexplore.exe,explorer.exe etc) have above problem and if run zabbix_agentd foreground zabbix_get can get ordinary value even though processes run as NOT SYSTEM user like below.
   
   
  Expected:
  zabbix_get can get ordinary value whether processes run as SYSTEM user or not.