Cannot create index with mapping or add mapping on 1.3.9

We recently upgraded our ES servers from 1.3.1 to 1.3.9. The migration/update was successful and everything in our existing indices is running great. However, we are getting a an error when trying to create a new index with a mapping or add a mapping to an existing index. Even the very simple create from the docs is failing.

curl -k -XPOST $BASE/test -d '{
"settings" : {
"number_of_shards" : 1
},
"mappings" : {
"type1" : {
"_source" : { "enabled" : false },
"properties" : {
"field1" : { "type" : "string", "index" : "not_analyzed" }
}
}
}
}'

Results in:
{"error":"RemoteTransportException[[svt4es02][inet[/9.37.16.10:51000]][indices/create]]; nested: MapperParsingException[mapping [type1]]; nested: ElasticsearchParseException[Failed to parse content to map]; nested: JsonParseException[Unexpected character (':' (code 58)): was expecting comma to separate OBJECT entries\n at [Source: UNKNOWN; line: 1, column: 86]]; ","status":400}

JVM details:
$ /usr/java7_64/jre/bin/java -version
java version "1.7.0"
Java(TM) SE Runtime Environment (build pap6470sr9fp20-20151106_01(SR9 FP20))
IBM J9 VM (build 2.6, JRE 1.7.0 AIX ppc64-64 Compressed References 20151019_272770 (JIT enabled, AOT enabled)