Global Login Item are deprecated remove them with this

rm_global_login.py

#!/usr/bin/python
'''
Pass in the Full path to the application as the first arg
for example  /usr/local/sbin/rm_global_login.py /Applicaitons/MunkiMenu.app
'''

import os
import sys
from LaunchServices import *

path = sys.argv[1:]

def main():
    if not path or not os.path.exists(path[0]):
        print 'no application at that path'
        sys.exit(1)

    loginItem = "file://%s" % path[0]
    loginItems = LSSharedFileListCreate(None, kLSSharedFileListGlobalLoginItems, None); 
       
    loginItemsArray,seed = LSSharedFileListCopySnapshot(loginItems, None);  
    for item in loginItemsArray:
        v,url,ref = LSSharedFileListItemResolve(item,0, None, objc.NULL)
        url = "%s" % url
        print url
        if url == loginItem:
            print 'removing %@' % url
            LSSharedFileListItemRemove(loginItems,item)
 
if __name__ == '__main__':
    main()