vagrant@ubuntu:/tmp/pear/temp/mongodb$ cat /usr/share/php/test/mongodb/tests/bson/bson-utcdatetime-001.diff 
001- string(31) "Thu, 20 Nov 2014 01:03:31 +0000"
001+ string(31) "Sun, 21 Dec 1969 15:43:25 +0000"
002- 1416445411987
002+ -893795693
004- Test#0 { "0" : { "$date" : 1416445411987 } }
004+ Test#0 { "0" : { "$date" : -893795693 } }
005- string(37) "{ "0" : { "$date" : 1416445411987 } }"
005+ string(34) "{ "0" : { "$date" : -893795693 } }"
006- string(37) "{ "0" : { "$date" : 1416445411987 } }"
006+ string(34) "{ "0" : { "$date" : -893795693 } }"
008- Test#1 { "0" : { "$date" : 1416445411987 } }
008+ Test#1 { "0" : { "$date" : -893795693 } }
009- string(37) "{ "0" : { "$date" : 1416445411987 } }"
009+ string(34) "{ "0" : { "$date" : -893795693 } }"
010- string(37) "{ "0" : { "$date" : 1416445411987 } }"
010+ string(34) "{ "0" : { "$date" : -893795693 } }