S3_PING fails to create a bucket

I tried to use S3_PING with a non-existent bucket configured, and channel creation failed:

Caused by: java.lang.IllegalArgumentException: Invalid Bucket Name: brian.stansberry-redhat.com_S3_PING
at org.jgroups.protocols.S3_PING$AWSAuthConnection.createBucket(S3_PING.java:248)
at org.jgroups.protocols.S3_PING.init(S3_PING.java:71)
at org.jgroups.stack.Configurator.initProtocolStack(Configurator.java:72)
at org.jgroups.stack.ProtocolStack.setup(ProtocolStack.java:299)
at org.jgroups.JChannel.init(JChannel.java:1578)
... 67 more

Saw this with 2.6.15 and with the 2.6.16 snapshot you gave me.