weird behavior with findMaterial

brokenmat.py

#!/usr/bin/env python
# coding=utf8
# for output, see https://gist.github.com/820741

import direct.directbase.DirectStart
from panda3d.core import MaterialCollection

model = loader.loadModel('testmodel.egg')

find_terms = ('playerColorA', 'playerColorB', 'nonsense', '')

print "all materials"
print model.findAllMaterials()
print
print

for t in find_terms:
	print "model.findMaterial('%s')" % t
	print model.findMaterial(t)
	print
	print

col = MaterialCollection(model.findAllMaterials())
for t in find_terms:
	print "col.findMaterial('%s')" % t
	print col.findMaterial(t)
	print
	print

run()

# for output, see https://gist.github.com/820741

output of script at https://gist.github.com/820741